Luminal impedance device with integrated circuit modules

ABSTRACT

Impedance devices with integrated circuit modules and method of using the same to obtain luminal organ information. In one embodiment, a device comprises an elongated body for at least partial insertion into a mammalian luminal organ and having a first conductor extending therethrough, a proximal electrical unit connected to the elongated body to deliver power along the first conductor, and a sensor substrate located at or near a distal end of the elongated body and comprising a circuit module operable and/or configured to direct the sizing portion to obtain sizing data and the pressure sensor to obtain pressure data, and facilitate transmission of the sizing data and/or the pressure data to the proximal electrical unit.

PRIORITY

The present application is related to, claims the priority benefit of,and is a U.S. continuation patent application of, U.S. patentapplication Ser. No. 16/674,990, filed Nov. 5, 2019 and issued as U.S.Pat. No. 11,382,528 on Jul. 12, 2022, which is related to, claims thepriority benefit of, and is a U.S. continuation patent application of,U.S. patent application Ser. No. 15/115,586, filed Jul. 29, 2016 andissued as U.S. Pat. No. 10,463,274 on Nov. 5, 2019, which is related to,claims the priority benefit of, and is U.S. 35 U.S.C. 371 national stagepatent application of, International Patent Application Serial No.PCT/US15/13939, filed Jan. 30, 2015, which is related to, and claims thepriority benefit of, U.S. Provisional Patent Application Ser. No.61/933,803, filed Jan. 30, 2014. The contents of each of theseapplications are hereby incorporated by reference in their entirety intothis disclosure.

BACKGROUND

Impedance devices, such as impedance wires and catheters, havedimensional requirements that require such devices to not only be smallenough to advance through mammalian luminal organs of various sizes, butalso small enough to be used in connection with other devices (such asguide catheters). The size requirements (such as overall devicediameter) generally constrain a developer of such a device when certaindevice functionality is desired.

Over several decades medical diagnostic and therapeutic interventionalprocedures have become less invasive due in part to the use of morepercutaneous surgical approaches, which access the intravascular systemand organs through the skin with a needle. Typically the first medicaldevice through these needles is a guidewire. The guidewire is navigatedto the location of interest by use of fluoroscopic imaging, MRI, orother imaging modalities. The guidewire, once navigated to the site ofinterest, becomes the access pathway for a variety of catheters neededto complete the percutaneous interventional procedure.

There exists a significant need to reduce the total cost of care forthese percutaneous procedures and the diseases they are treating. Recentsolutions to this need include, among other things, an increase in smartdevices to quickly, accurately and intelligently diagnose and inform theinterventional procedure. This solution includes adding sensors toguidewires. A clinical application such as angioplasty/stenting to opena vessel stenosis may ideally use intravascular pressure sensing todetermine pressure changes in a vessel of interest and the applicabilityof therapy. Once a pressure gradient or fraction flow reserve isdetermined to be significant, a clinician may want to use intravascularsensors to more accurately size the vessel, determine location of lipidpools, determine thickness of lipid pool caps, determine force beingapplied to tissues, or even assess post therapy information. Ideally allof this sensor information will be derived from the guidewire as thecommon tool which initially accesses and remains across the site ofinterest.

Another solution to this reduced cost clinical need is the creation ofsmaller interventional devices. This includes devices for radial access,reducing hospital stays. It also includes treating problems earlier inmore vascular distal locations. The need for smaller percutaneousdevices includes guidewires. This is not easily done however; becauseoften the entire guidewire cross section needs to consist of a highmodulus material such as stainless steel in order to provide sufficientsupport for diagnostic and/or therapy delivery catheters. Coronaryguidewires for instance are 0.014″ in diameter and most of the guidewirelength is constructed of a core which is close to 0.014″ in diameter,and often these are not stiff enough in lateral bending. Also, this samemaximizing of Young's modulus and diameter translates into improvedtorque and steerability performance, which is critically important inguidewires since it is this device that the clinician uses to guideaccess to the site of interest.

Adding the needed sensor conductors over the length of the guidewire cantake cross-sectional area and thus reduce the lateral stiffness,torsional stiffness and torsional control of the guidewire, andtherefore increase guidewire delivery time, catheter delivery time,device cost and possibly total cost of care. An example of this is themarketed pressure sensing guidewire made of hypo tubes. The hypo tube isused instead of a guidewire core with a full cross section of metal sosensor conductor wires can be run down the inside of the hypo tube core,from the proximal end of the guidewire to the distal tip of theguidewire enabling the pressure sensor. Unfortunately the use of a hypotube for the guidewire core gives this device undesirable lateralstiffness and clinical device delivery characteristics.

Furthermore, currently contemplated guidewires using pressure sensorsare generally limited to enabling the dual combination of the necessarymechanical characteristics and pressure sensing. But vessel sizing,imaging, temperature, or other sensing modalities, which may furtherminimize procedure cost and improve therapeutic outcomes, are notenabled, either alone or in combination.

There remains a need for a higher performance guidewire that is capableof quickly and accurately measuring multiple biological metrics whilemaximizing high performance mechanical characteristics. In view of thesame, impedance devices, and systems incorporating the same, havingdesired functionality with fewer parts than would normally be requiredand/or having components/componentry small enough to permit desireddevice operation, would be well received in the marketplace and solve anumber of problems facing impedance device developers.

BRIEF SUMMARY

In an exemplary embodiment of an impedance device of the presentdisclosure, the device comprises an elongated body configured for atleast partial insertion into a mammalian luminal organ of a patient, theelongated body having a first conductor extending therethrough, aproximal electrical unit operably connected to the elongated body andconfigured to deliver power along the first conductor, and a sensorsubstrate located at or near a distal end of the elongated body, thesensor substrate comprising a circuit module operably coupled to asizing portion and a pressure sensor that are powered directly orindirectly from the power delivered through the first conductor, thecircuit module operable and/or configured to a) direct the sizingportion to obtain sizing data, b) direct the pressure sensor to obtainpressure data, and c) facilitate transmission of the sizing data and/orthe pressure data to the proximal electrical unit. In at least oneembodiment, the first conductor comprises a single conductor, andwherein the circuit module is operable to direct operation of the sizingportion to obtain sizing data, to direct the pressure sensor to obtainpressure data, and to facilitate transmission of the sizing data and/orthe pressure data to the proximal electrical unit using the powerdelivered along the first conductor. In at least one embodiment, thesensor substrate has at least one of a cross-sectional area and/or adiameter corresponding to a cross-sectional area and/or a diameter ofthe elongated body at a first location. In at least one embodiment, thesensor substrate further comprises a capacitor configured to obtain thepower from the proximal electrical unit. In at least one embodiment, thesensor substrate further comprises a distal power source, the distalpower source configured to charge the capacitor.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is powered from the power from theproximal electrical unit. In at least one embodiment, the circuit moduleis powered by a distal power source of the sensor substrate, the distalpower source configured to power the circuit module using the powerdelivered through the first conductor and/or from a capacitor coupled tothe distal power source that is configured to receive the powerdelivered through the first conductor. In at least one embodiment, thesizing portion comprises a pair of detection electrodes positioned inbetween a pair of excitation electrodes, the pair of excitationelectrodes configured to generate an electric field detectable by thepair of detection electrodes. In at least one embodiment, the sizingportion is directly coupled to the sensor substrate. In at least oneembodiment, the sizing portion is positioned upon a portion of theelongated body distal to the sensor substrate.

In an exemplary embodiment of an impedance device of the presentdisclosure, the sizing portion and the pressure sensor are each operablyconnected to a multiplexer positioned upon or within the sensorsubstrate. In at least one embodiment, a first amplifier is positionedbetween the sizing portion and the multiplexer, and wherein at least asecond amplifier is positioned between the pressure sensor and themultiplexer, the first amplifier configured to amplify the sizing dataand the second amplifier configured to amplify the pressure data. In atleast one embodiment, the multiplexer is configured to receive sizingdata from the sizing portion and pressure data from the pressure sensorand is further configured to separately transmit the sizing data and thepressure data to the circuit module. In at least one embodiment, themultiplexer is configured to receive sizing data from the sizing portionand pressure data from the pressure sensor and is further configured tofirst transmit the sizing data and the pressure data to ananalog-to-digital converter positioned upon or within the sensorsubstrate for transmission to the circuit module. In at least oneembodiment, the analog-to-digital converter is configured to convert thesizing data and the pressure data from analog data to digital data.

In an exemplary embodiment of an impedance device of the presentdisclosure, the sensor substrate facilitates transmission of the sizingdata and/or the pressure data to the proximal electrical unit by way ofa metallic element coupled to the sensor substrate, wherein the metallicelement is configured to transmit the sizing data and/or the pressuredata through tissue adjacent to the mammalian luminal organ to a padpositioned upon skin of the patient. In at least one embodiment, themetallic element comprises a distal ground coupled to the sensorsubstrate. In at least one embodiment, the metallic element comprises anelectrode of the sizing portion. In at least one embodiment, themetallic element comprises the pressure sensor. In at least oneembodiment, the metallic element comprises a transmitter coupled to orwithin the sensor substrate.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a first switch positionedbetween the elongated body and the circuit module. In at least oneembodiment, the device further comprises a second switch positionedbetween a distal power source of the sensor substrate and a distalground coupled to the sensor substrate. In at least one embodiment,power from the proximal electrical unit is delivered by a power sourceof the proximal electrical unit. In at least one embodiment, theelongated body further has a second conductor extending therethrough,wherein the power is delivered from the proximal electrical unit to thesensor substrate using the first conductor, and wherein the sizing dataand/or the pressure data is transmitted from the sensor substrate to theproximal electrical unit using the second conductor.

In an exemplary embodiment of an impedance device of the presentdisclosure, the elongated body comprises a proximal segment having thefirst conductor extending therethrough, the proximal segment configuredto connect to an inner segment. In at least one embodiment, the proximalsegment is connected to the inner segment, and wherein the inner segmentis configured to connect to a distal segment. In at least oneembodiment, the sensor substrate is configured to fit within the innersegment.

In an exemplary embodiment of an impedance device of the presentdisclosure, the first conductor is positioned within a proximal segmentof the elongated body, and wherein the proximal segment is connected toan inner segment which is further connected to a distal segment. In atleast one embodiment, the inner segment comprises the sensor substrate.In at least one embodiment, the circuit module and the pressure sensorare configured to fit within a component housing, and wherein thecomponent housing is configured to fit within the inner segment. In atleast one embodiment, the impedance device further comprises a capacitorconnected to the circuit module. In at least one embodiment, thecapacitor is configured to fit within the component housing. In at leastone embodiment, the impedance device further comprises a transfercircuit connected to at least one of the pressure sensor, the circuitmodule, and the capacitor, the transfer circuit configured toelectrically connect to at least one element positioned thereto.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a wrap configured to wraparound at least part of the elongated body at a first location. In atleast one embodiment, the sizing portion comprises a plurality ofelectrodes configured to obtain the sizing data, and wherein theplurality of electrodes are coupled to or formed as part of the wrap. Inat least one embodiment, when the wrap is positioned around at leastpart of the elongated body at the first location, at least one of theplurality of electrodes is electrically coupled to the circuit module.In at least one embodiment, the first conductor is positioned within aproximal segment of the elongated body, and wherein the proximal segmentis connected to an inner segment which is further connected to a distalsegment. In at least one embodiment, the circuit module and the pressuresensor are configured to fit within a component housing, and wherein thecomponent housing is configured to fit within an inner segment.

In an exemplary embodiment of an impedance device of the presentdisclosure, the power delivered from the proximal electrical unit isalternating current power, wherein the circuit module is furtheroperable to rectify the alternating current to generate direct currentpower to operate the sizing portion and/or the pressure sensor. In atleast one embodiment, the circuit module is further operable to regulatethe direct current power to reduce power ripples and to provide aconstant voltage supply to the sizing portion and/or the pressuresensor. In at least one embodiment, the circuit module is furtheroperable to modulate a carrier wave used to transmit the sizing dataand/or the pressure data to the proximal electrical unit. In at leastone embodiment, the circuit module is further operable to detect aninterruption of the power from the proximal electrical unit. In at leastone embodiment, the circuit module is further operable to controloperation of the sizing portion, the pressure sensor, a temperaturesensor within the sensor substrate that is operable to obtaintemperature data, and a capacitor within the sensor substrate that isoperably coupled to a power source within the sensor substrate.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable to generatediagnostic information using the sizing data and/or the pressure datafor transmission to the proximal electrical unit. In at least oneembodiment, the circuit module is further operable to produce offsetvoltages to the sizing portion and/or the pressure sensor and to anyamplifiers connected to the sizing portion and/or the pressure sensor.In at least one embodiment, the sensor substrate further comprises apower source coupled to a capacitor, a first switch connected to aground, and a second switch connected to the first conductor, andwherein the circuit module is further operable to control operation ofthe first switch and/or the second switch during and after operation ofthe sizing portion and/or the pressure sensor. In at least oneembodiment, the circuit module is further operable to control deliveryof the direct current power to one or more excitation electrodes of thesizing portion. In at least one embodiment, the circuit module isfurther operable to control delivery of the direct current power to oneor more excitation electrodes of the sizing portion.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable to controlamplification of the sizing data and/or the pressure data. In at leastone embodiment, the control is performed by the circuit module and oneor more amplifiers connected to the sizing portion and/or the pressuresensor. In at least one embodiment, the circuit module is furtheroperable to sample the sizing data from the sizing portion and/or thepressure data from the pressure sensor at correct instances. In at leastone embodiment, the sizing data from the sizing portion and the pressuredata from the pressure sensor are analog signals, and wherein thecircuit module is further operable to convert the analog signals todigital signals. In at least one embodiment, the conversion is performedby the circuit module and an analog to digital converter directly orindirectly connected to the circuit module.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable to control storage ofthe sizing data and/or the pressure data. In at least one embodiment,the storage is performed by the circuit module and memory directly orindirectly connected to the circuit module. In at least one embodiment,the circuit module is further operable to regulate transmission of thesizing data and/or the pressure data to the proximal electrical unit. Inat least one embodiment, the regulation is performed by the circuitmodule and a wired or wireless communication module directly orindirectly connected to the circuit module.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable to interface with oneor more radio frequency components within the sensor substrate torecover the power delivered by the proximal electrical unit using radiofrequency electromagnetic waves. In at least one embodiment, the circuitmodule is further operable to interface with one or more radio frequencycomponents within the sensor substrate to transmit the sizing dataand/or the pressure data to the proximal electrical unit using radiofrequency electromagnetic waves. In at least one embodiment, thepressure sensor is further operable to obtain temperature data. In atleast one embodiment, the sensor substrate further comprises atemperature sensor, and wherein the circuit module is further operableand/or configured to direct the temperature sensor to obtain temperaturedata and to facilitate transmission of the temperature data to theproximal electrical unit. In at least one embodiment, the elongated bodyand the sensor substrate each have an outer diameter of 0.014″ or less.

In an exemplary embodiment of an impedance device of the presentdisclosure, the elongated body and the sensor substrate are configuredas a guide wire. In at least one embodiment, the impedance device isconfigured as a guide wire. In at least one embodiment, the proximalelectrical unit is configured as a handle for the elongated body. In atleast one embodiment, the proximal electrical unit is configured as acomputer console. In at least one embodiment, the circuit module isoperable and/or configured to facilitate transmission of the sizing dataand/or the pressure data to the proximal electrical unit by directingoperation of a wireless communication module configured to wirelesslytransmit the sizing data and/or the pressure data to the proximalelectrical unit or a component coupled thereto. In at least oneembodiment, the wireless communication module is configured to wirelesstransmit the sizing data and/or the pressure data using radio frequencysignals.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable and/or configured totemporarily cease delivery of power to the sizing portion and thepressure sensor during generation of the sizing data and/or the pressuredata. In at least one embodiment, the circuit module is further operableand/or configured to temporarily cease transmission of the powerdelivered through the first conductor to the sensor substrate duringgeneration of the sizing data and/or the pressure data. In at least oneembodiment, the impedance device is configured so that when the circuitmodule identifies a temporary cessation of power from the proximalelectrical unit, the sizing portion operates to obtain the sizing dataand the pressure sensor operates to obtain the pressure data.

In an exemplary embodiment of an impedance device of the presentdisclosure, a microprocessor with the proximal electrical unit regulatesthe delivery of power to the first conductor. In at least oneembodiment, when the microprocessor temporarily ceases delivery of powerto the first conductor, the sizing portion is triggered to obtain thesizing data and/or the pressure sensor is triggered to obtain thepressure data. In at least one embodiment, the circuit module is furtheroperable and/or configured to instruct the microprocessor to temporarilycease delivery of power to the first conductor. In at least oneembodiment, the circuit module is further operable and/or configured toidentify the temporary cessation of delivery of power to the firstconductor. In at least one embodiment, the circuit module is furtheroperable and/or configured to direct the sizing portion to obtain thesizing data and/or the pressure sensor to obtain the pressure data afteridentifying the temporary cessation of delivery of power to the firstconductor.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module is further operable to capture the sizingdata and the pressure data prior to facilitating transmission of thesizing data and/or the pressure data to the proximal electrical unit. Inat least one embodiment, the circuit module facilitates transmission ofthe sizing data and/or the pressure data to the proximal electrical unitduring a time when power from the proximal electrical unit to the firstconductor is temporarily stopped. In at least one embodiment, thecircuit module is further operable and/or configured to instruct theproximal electrical unit to temporarily stop the delivery of power tothe first conductor. In at least one embodiment, the circuit module isfurther operable and/or configured to identify that the proximalelectrical unit has temporarily stopped the delivery of power to thefirst conductor.

In an exemplary embodiment of an impedance device of the presentdisclosure, the circuit module directs the sizing portion to obtainsizing data at the same time it directs the pressure sensor to obtainpressure data. In at least one embodiment, the circuit module directsthe sizing portion to obtain sizing data at a separate time from when itdirects the pressure sensor to obtain pressure data. In at least oneembodiment, the circuit module directs the sizing portion to obtainsizing data based upon a first trigger, the first trigger selected fromthe group consisting of a temperature trigger from the pressure sensorand a power trigger from the proximal electrical unit. In at least oneembodiment, the temperature trigger is obtained by a half-Wheatstonebridge of the pressure sensor based upon a threshold temperaturedetected within the mammalian luminal organ. In at least one embodiment,the temperature trigger is obtained by the pressure sensor due to atemperature change from an injected bolus of solution. In at least oneembodiment, the temperature trigger is obtained by the pressure sensordue to an increase in pressure sensor temperature due to the presence ofblood.

In an exemplary embodiment of an impedance device of the presentdisclosure, the impedance device forms part of a system, the systemfurther comprising a pad configured for attachment to skin of thepatient and further configured to receive the sizing data and/or thepressure data from the sensor substrate through tissue of the patient.In at least one embodiment, the sizing data and/or the pressure data canbe transmitted to the proximal electrical unit by way of a pad wirecoupled to the pad and the proximal electrical unit. In at least oneembodiment, the system further comprises a data acquisition andprocessing system configured to receive the sizing data and/or thepressure data from the pad.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device comprises an elongated body configured for atleast partial insertion into a mammalian luminal organ of a patient, theelongated body having a single conductor extending therethrough, aproximal electrical unit operably connected to the elongated body andconfigured to deliver power to the single conductor; and a sensorsubstrate located at or near a distal end of the elongated body, thesensor substrate comprising a circuit module operably coupled to asizing portion and a pressure sensor that are powered directly orindirectly from the power delivered through the single conductor, thecircuit module operable and/or configured to a) direct the sizingportion to obtain sizing data, b) direct the pressure sensor to obtainpressure data, and c) facilitate transmission of the sizing data and/orthe pressure data to the proximal electrical unit, wherein a) and b) areperformed upon the circuit module identifying that power through thesingle conductor from the proximal electrical unit has temporarilystopped.

In at least one embodiment, the circuit module is also coupled to atemperature sensor, and wherein the circuit module is operable and/orconfigured to direct the temperature sensor to obtain temperature data.

In at least one embodiment, transmission of the sizing data and/or thepressure data to the proximal electrical unit is performed upon thecircuit module identifying that power through the single conductor fromthe proximal electrical unit has temporarily stopped.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device comprises an elongated body configured for atleast partial insertion into a mammalian luminal organ of a patient, theelongated body having a first conductor extending therethrough, aproximal electrical unit operably connected to the elongated body andconfigured to deliver power along the first conductor, and a sensorsubstrate located at or near a distal end of the elongated body, thesensor substrate comprising a circuit module operably coupled to a firstsensor type and a second sensor type, the circuit module operable and/orconfigured to a) direct the first sensor type to obtain a first datatype, b) direct the second sensor type to obtain a second data type, andc) facilitate transmission of the first data type and/or the second datatype to the proximal electrical unit. In at least one embodiment, thefirst sensor type and the second sensor type are each selected from thegroup consisting of a sizing sensor, a pressure sensor, a temperaturesensor, a pH sensor, a flow sensor, a velocity sensor, and a thermistor,wherein the first data type and the second data type are each selectedfrom the group consisting of sizing data from the sizing sensor,pressure data from the pressure sensor, temperature data from thepressure sensor, temperature data from the temperature sensor, pH datafrom the pH sensor, flow data from the flow sensor, velocity data fromthe velocity sensor, and temperature data from the thermistor, andwherein the first sensor type is different from the second sensor type.

In at least one embodiment, the circuit module is further operablycoupled to a third sensor type, the circuit module is further operableand/or configured to obtain a third data type and to facilitatetransmission of the third data type to the proximal electrical unit, thethird sensor type is selected from the group consisting of a sizingsensor, a pressure sensor, a temperature sensor, a pH sensor, a flowsensor, a velocity sensor, and a thermistor, the first third data typeis each selected from the group consisting of sizing data from thesizing sensor, pressure data from the pressure sensor, temperature datafrom the pressure sensor, temperature data from the temperature sensor,pH data from the pH sensor, flow data from the flow sensor, velocitydata from the velocity sensor, and temperature data from the thermistor,and wherein the third sensor type is different from the first sensortype and the second sensor type.

In at least one embodiment of a method of the present disclosure, themethod comprises the steps of inserting a portion of an impedance deviceinto a luminal organ of a patient, the impedance device comprising anelongated body configured for at least partial insertion into theluminal organ, the elongated body having a first conductor extendingtherethrough, a proximal electrical unit operably connected to theelongated body and configured to deliver power through the firstconductor, and a sensor substrate located at or near a distal end of theelongated body, the sensor substrate comprising a circuit moduleoperably coupled to a sizing portion and a pressure sensor andconfigured to direct operation of the sizing portion to obtain sizingdata and the pressure sensor to obtain pressure data and furtherconfigured to facilitate transmission of the sizing data and/or thepressure data to the proximal electrical unit by way of the elongatedbody, operating the impedance device to obtain the sizing data and thepressure data within the luminal organ, transmitting one of the sizingdata or the pressure data to the proximal electrical unit, and if thesizing data was transmitted to the proximal electrical unit,transmitting the pressure data to the proximal electrical unit, or ifthe pressure data was transmitting to the proximal electrical unit,transmitting the sizing data to the proximal electrical unit. In atleast one embodiment, the sizing data and/or the pressure data istransmitted to the proximal electrical unit by first transmitting thesizing data and/or the pressure data through tissue of the patient to apad positioned upon the patient's skin, wherein the pad is operablyconnected to the proximal electrical unit. In at least one embodiment,the first conductor comprises at least two conductors, wherein the poweris delivered from the proximal electrical unit to the sensor substrateusing one of the at least two conductors, and wherein the sizing dataand/or the pressure data is transmitted from the sensor substrate to theproximal electrical unit using the other of the at least two conductors.In at least one embodiment, the operating step is performed after thecircuit module identifies that the proximal electrical unit hastemporarily ceased delivery of the power to the first conductor.

In an exemplary embodiment of a device and/or a system of the presentdisclosure, the device and/or system comprises one or more of thefollowing components, features, and/or functionalities: an elongatedbody, which can be a wire (insulated or non-insulated), a catheter, ahypotube, and/or another elongated body known or developed in themedical arts relating to and for use with blood vessel entry andnavigation; a circuit module, which can be formed in, placed/positionedin, or placed/positioned on, part of device; a conductive element (suchas a conductive wire, for example), which can be present inside of,formed within, or positioned or coupled to an outside of, elongatedbody, and extend from circuit module to a location proximal to circuitmodule, such as a data acquisition and processing system; a dataacquisition and processing system configured to send a signal (dataand/or power) to a circuit module and further configured to receive datafrom the device; a sizing portion, comprising, for example, a pluralityof electrodes used to obtain cross-sectional area, diameter, and/orother measurements of luminal organ geometry; one or more detectionelectrodes positioned in between two excitation electrodes; a pressuresensor; a temperature sensor; another sensor (that is not a pressure ortemperature sensor); one or more wires used to connect the variouselectrodes and/or sensors to the circuit module; a pad configured to bepositioned upon and/or generally external to the patient, so that signaldata can extend from the electrodes and/or sensors, through thebloodstream, to the pad, and ultimately to, for example, a dataacquisition and processing system; a pad wire for connection to a padand to a data acquisition and processing system; and/or a microarrayhaving at least one electrode or sensor.

In an exemplary embodiment of a device and/or a system of the presentdisclosure, the device and/or system is operational to perform one ormore of the following procedures/tasks: obtain conductance, pressure,and/or temperature data within a mammalian luminal organ; determiningthe size (cross-sectional area or diameter, for example) of a mammalianluminal organ; determining parallel tissue conductance within amammalian luminal organ; navigation of said device(s) within a luminalorgan; determining the location of one or more body lumen junctionswithin a mammalian luminal organ; determining profiles of a luminalorgan; ablating a tissue within a mammalian patient; removing stenoticlesions from a vessel; determining the existence, potential type, and/orvulnerability of a plaque within a luminal organ; determining phasiccardiac cycle measurements; determining vessel compliance; determiningthe velocity of a fluid flowing through a mammalian luminal organ;sizing valves using impedance and balloons, such as sizing a valveannulus for percutaneous valves; detecting and/or removing contrast frommammalian luminal organs; determining fractional flow reserve; placingleads within a mammalian luminal organ; ablation of relatively smallveins for Endovascular Laser Therapy (EVLT) for treatment of venousinsufficiency of varicose veins and/or other cosmetic procedures; and/ornavigation through a portion of a patient's urological system, such aswithin a ureter, to potentially identify a stenosis or a sizeabnormality. Various devices and/or systems of the present disclosureare configured and/or operational as referenced herein.

In an exemplary embodiment of a device of the present disclosure, thedevice comprises an elongated body configured for insertion into amammalian luminal organ, at least one sensor coupled to the elongatedbody and configured to obtain sensor data within the mammalian luminalorgan, and a circuit module coupled to the elongated body and configuredto receive the sensor data from at least one of the at least one sensor.In another embodiment, the elongated body is selected from the groupconsisting of a wire, a catheter, and a hypotube.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a conductive element coupled tothe circuit module and configured to transmit current to the circuitmodule. In another embodiment, the conductive element is furtherconfigured to transmit a signal to the circuit module. In yet anotherembodiment, the circuit module is configured to transmit a signal to theconductive element, the signal at least partially comprising the sensordata or a form thereof. In an additional embodiment, the conductiveelement is further configured to transmit a signal from the circuitmodule to a data acquisition and processing system.

In an exemplary embodiment of an impedance device of the presentdisclosure, the at least one sensor is selected from the groupconsisting of an excitation electrode, a detection electrode, a pressuresensor, and a temperature sensor. In an additional embodiment, the atleast one sensor comprises two or more sensors (also referred to as a“sensor set”), and wherein each of the two or more sensors are selectedfrom the group consisting of one or more excitation electrodes, one ormore detection electrodes, one or more pressure sensors, and one or moretemperature sensors. In yet an additional embodiment, the at least onesensor comprises a sizing portion, the sizing portion comprising atleast the at least one sensor and configured to obtain luminal organsize information using impedance.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a wire coupled to the at leastone sensor and the circuit module, the wire configured to transmit thesensor data from the at least one sensor to the circuit module. Inanother embodiment, the device is configured so that the sensor data canbe transmitted from the at least one sensor through a portion of abloodstream of a patient and to a pad positioned upon or generallyexternal to the patient. In yet another embodiment, the device isconfigured so that the sensor data can be transmitted from the at leastone sensor to the control module and through a portion of a bloodstreamof a patient and to a pad positioned upon or generally external to thepatient.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a microarray coupled to theelongated body, wherein the at least one sensor is coupled to or formspart of the microarray. In another embodiment, the device furthercomprises a microarray coupled to the elongated body, wherein themicroarray comprises at least one additional sensor. In yet anotherembodiment, the sensor data can be received wirelessly by the controlmodule.

In an exemplary embodiment of an impedance device of the presentdisclosure, the device further comprises a balloon coupled to theelongated body and positioned so that at least one of the at least onesensors is positioned within the balloon.

In an exemplary embodiment of a device of the present disclosure, thedevice comprises an elongated body configured for insertion into amammalian luminal organ, at least one sensor coupled to the elongatedbody and configured to obtain sensor data within the mammalian luminalorgan, a circuit module coupled to the elongated body and configured toreceive the sensor data from at least one of the at least one sensor, aconductive element coupled to the circuit module and configured totransmit current to the circuit module and further configured totransmit a signal to and/or from the circuit module, and a microarraycoupled to the elongated body, wherein the at least one sensor iscoupled to or forms part of the microarray.

In an exemplary embodiment of a method of the present disclosure, themethod comprises the steps of positioning at least part of a devicewithin a luminal organ of a patient, the device comprising an elongatedbody configured for insertion into a mammalian luminal organ, at leastone sensor coupled to the elongated body and configured to obtain sensordata within the mammalian luminal organ, and a circuit module coupled tothe elongated body and configured to receive the sensor data from atleast one of the at least one sensor, operating the at least one sensorwithin the luminal organ to obtain the sensor data, and operating thecontrol module to obtain the sensor data from the at least one sensor.In another embodiment, the sensor data comprises data selected from thegroup consisting of conductance data, pressure data, and temperaturedata. In an additional embodiment, the at least one sensor comprises oneor more sensors forming a sizing portion, and wherein the step ofoperating the control module further comprises activating at least oneof the one or more sensors to generate an electric field within themammalian luminal organ.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed embodiments and other features, advantages, anddisclosures contained herein, and the matter of attaining them, willbecome apparent and the present disclosure will be better understood byreference to the following description of various exemplary embodimentsof the present disclosure taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 shows a device, according to an exemplary embodiment of thepresent disclosure;

FIG. 2 shows a circuit using a device and a pad, according to anexemplary embodiment of the present disclosure;

FIG. 3 shows a device using a circuit module as an excitation electrode,according to an exemplary embodiment of the present disclosure;

FIG. 4 shows a device having a microassembly, according to an exemplaryembodiment of the present disclosure;

FIG. 5 shows a device, according to an exemplary embodiment of thepresent disclosure;

FIG. 6 shows a device having a microassembly, according to an exemplaryembodiment of the present disclosure;

FIGS. 7, 8, and 9 show devices and systems useful to obtain data,according to exemplary embodiments of the present disclosure;

FIG. 10 shows a carrier wave and components thereof, according to anexemplary embodiment of the present disclosure;

FIG. 11 shows a flowchart of events, according to an exemplaryembodiment of the present disclosure;

FIG. 12 shows a device having two conductive elements, according to anexemplary embodiment of the present disclosure;

FIG. 13 shows a flowchart of events, according to an exemplaryembodiment of the present disclosure;

FIGS. 14, 15, 16, and 17 show operations of electrodes of exemplarydevices, according to exemplary embodiments of the present disclosure;

FIG. 18 shows components of a sensor substrate, according to anexemplary embodiment of the present disclosure; and

FIG. 19 shows a device and system and the directional flow of power anddata signals, according to an exemplary embodiment of the presentdisclosure.

FIG. 20 shows a listing of data packages in connection with datatransmission, according to an exemplary embodiment of the presentdisclosure;

FIG. 21 shows logic sequences of different data values, according to anexemplary embodiment of the present disclosure;

FIG. 22 shows components of a system used for a study to test the same,according to an exemplary embodiment of the present disclosure;

FIG. 23 shows an image of a vein of a tested animal, according to anexemplary embodiment of the present disclosure;

FIG. 24 shows a chart of cross sectional area relating to conductance,according to an exemplary embodiment of the present disclosure;

FIG. 25 shows a chart of voltage over time, according to an exemplaryembodiment of the present disclosure;

FIG. 26 shows an exploded perspective view of components of a device,according to an exemplary embodiment of the present disclosure;

FIG. 27 shows a perspective view of elements of a device, according toan exemplary embodiment of the present disclosure;

FIG. 28A shows a cross-sectional view of a portion of a device,according to an exemplary embodiment of the present disclosure;

FIG. 28B shows a cut-away view of a device with various componentstherein, according to an exemplary embodiment of the present disclosure;

FIGS. 28C and 28D show side views of a device, according to exemplaryembodiments of the present disclosure;

FIG. 29A shows a perspective view of part of a device with a wrapthereon, according to an exemplary embodiment of the present disclosure;

FIG. 29B shows a perspective view of a wrap, according to an exemplaryembodiment of the present disclosure;

FIG. 29C shows a magnified view of a wrap, according to an exemplaryembodiment of the present disclosure;

FIGS. 29D and 29E show side views (or top and bottom views) of a wrap,according to exemplary embodiments of the present disclosure;

FIG. 30A shows a side cut-away view of a component housing withcomponents therein, according to an exemplary embodiment of the presentdisclosure;

FIG. 30B shows a perspective view of a component housing with componentstherein, according to an exemplary embodiment of the present disclosure;

FIG. 30C shows a side view, and FIG. 30D shows a cross-sectional view,of a component housing with componentry therein, according to exemplaryembodiments of the present disclosure;

FIG. 30E shows a cut-away view of a component housing with componentstherein, according to an exemplary embodiment of the present disclosure;

FIGS. 31 and 32 show device schematics, according to exemplaryembodiments of the present disclosure; and

FIGS. 33 and 34 show devices and systems useful to obtain data,according to exemplary embodiments of the present disclosure.

An overview of the features, functions and/or configurations of thecomponents depicted in the various figures will now be presented. Itshould be appreciated that not all of the features of the components ofthe figures are necessarily described. Some of these non-discussedfeatures, such as various couplers, etc., as well as discussed featuresare inherent from the figures themselves. Other non-discussed featuresmay be inherent in component geometry and/or configuration.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the embodimentsillustrated in the drawings, and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of this disclosure is thereby intended.

FIG. 1 shows an exemplary distal portion of a device 100 of the presentdisclosure. As shown therein, device 100 comprises an elongated body102, which can be a wire (insulated or non-insulated), a catheter, ahypotube, and/or another elongated body known or developed in themedical arts relating to and for use with blood vessel entry andnavigation. A circuit module 104 (which may also be referred to hereinas a control module), as shown in FIG. 1 , can be formed in,placed/positioned in, or placed/positioned on, part of device 100 (whichmay also be referred to herein as impedance devices given theirimpedance operation/functionality). In embodiments of devices 100configured as conductive wires, elongated body 102 would connect tocircuit module 104 so to permit signal data to travel from elongatedbody 102 to circuit module 104, and in some embodiments, to allow signaldata to travel from circuit module 104 to elongated body 102. Inembodiments of devices 100 configured as non-conductive wires,catheters, hypotubes, or other bodies, a conductive element 106 (such asa conductive wire, for example), can be present inside of, formedwithin, or positioned or coupled to an outside of, elongated body 102,and extend from circuit module 104 to a location proximal to circuitmodule, such as a data acquisition and processing system 250 (anexemplary console, as shown in FIG. 2 ). In other embodiments,conductive element 106 may be formed as a coil, and use of a firstconductor (such as elongated body 102) and a second conductor (such asconductive element) would allow for the transmission of power/currentand the transmission of data in a bidirectional manner using only device100.

A distal section 108 of device 100 would extend from circuit module 104to a distal end 110 of device 100, as shown in FIG. 1 . Distal section108, in various embodiments, would include a sizing portion 120,comprising, for example, a plurality of electrodes (such as electrodes122, 124, 126, 128 referenced in detail herein) used to obtaincross-sectional area, diameter, and/or other measurements of luminalorgan geometry when device 100 is positioned within a luminal organ.Sizing portion 120, in various embodiments, may include one or moreelectrodes, such as, for example, two detection electrodes (122, 124,also shown as “D” in FIG. 1 ) positioned in between two excitationelectrodes (126, 128, also shown as “E” in FIG. 1 ), along distalsection 108 of device 100. Additional sensors or electrodes, such as apressure sensor (an exemplary “other sensor 130” shown as “P”), and/or atemperature sensor (another exemplary “other sensor 130” shown as “T”),as shown in FIG. 1 , can also be positioned along or within device 100,such as at distal section 108 or another portion of device 100. Othertypes of sensors 130 can be used, such as, for example, pH sensors, flowsensors, velocity sensors, thermistors, and/or other types of chemicalsensors, and be included with device 100 as referenced herein withrespect to pressure and/or temperature sensors 100. In addition, lessthan two detection electrodes 122, 124 and/or less than two excitationelectrodes 126, 128 may be used to obtain sizing data, such as by usingtwo or three overall electrodes for sizing.

Wires 150, as shown in FIG. 1 , can be used to individually connect thevarious electrodes and/or sensors to circuit module 104. For example,and in various embodiments, one wire 150 can be used to connectexcitation electrode 126 to circuit module 104, while another wire 150can be used to connect detection electrode 122 to circuit module 104. Inat least one embodiment, one connection is used to connect excitationelectrode 126 to excitation electrode 128 (using one wire 150) and tothen connect excitation electrode 128 to circuit module 104 (using thesame wire 150 or another wire 150 connected in series), so that circuitmodule 104 is connected to excitation electrode 126 and 128 from onewire 150 extending from circuit module 104. Similarly, and in variousembodiments, one connection is used to connect detection electrode 122to detection electrode 124 (using one wire 150) and to then connectdetection electrode 124 to circuit module 104 (using the same wire 150or another wire 150 connected in series), so that circuit module 104 isconnected to detection electrodes 122 and 124 from one wire 150extending from circuit module 104. In such embodiments (where oneconnection is used to connect excitation electrodes 126, 128 and/ordetection electrodes 122, 124, those pairs of electrodes wouldeffectively act as a single electrode (as the two would be shortedtogether), and another electrode, such as a pad 200 (referenced infurther detail below) would act as a return electrode. Such embodimentscould be used for navigation (as the elements used for excitation(excitation electrodes 126, 128) and voltage recording (detectionelectrodes 122, 124) would be “unipolar” to the body surface), while thetraditional tetrapolar embodiments (having electrodes 122, 124, 126, and128 each connected to separate wires 150) could be used for sizing, asreferenced herein. Excitation electrodes 126, 128 can, when inoperation, excite an electric field within a mammalian luminal organ,which can be detected by detection electrodes 122, 124, so thatconductance measurements can be obtained using impedance.

At least one embodiment of a device 100 of the present disclosure wouldinclude a circuit module 104 and a distal section 108 distal to circuitmodule, and further comprise a sizing portion 120 and at least oneadditional sensor 130, such as, for example, a temperature sensor and/ora pressure sensor.

So that data can be obtained from the various electrodes and/or sensorsreferenced herein, a signal (through a circuit) can be transmittedeither back through elongated body 102 or conductive element 106, or viaa pad 200 positioned upon and/or generally external to the patient, sothat signal data can extend from the electrodes and/or sensors, throughthe bloodstream, to pad 200, and ultimately to, for example, dataacquisition and processing system 250, as shown in FIG. 2 . Pad 200, insuch an embodiment, would be coupled to data acquisition and processingsystem 250 by way of a pad wire 202, for example, so that the overallsignal circuit is complete. In various embodiments, device 100 cancouple directly to data acquisition and processing system 250, or can beconnected to data acquisition and processing system 250 by way of anexemplary coupler 210, as shown in FIG. 2 .

Using such an exemplary device 100, or an exemplary system 300(comprising at least device 100 and at least one other item, such as apad 200 and/or data acquisition and processing system 250, for example),data relating to sizing (vessel cross-sectional area and/or geometry)can be obtained, along with additional data, such as relating topressure or temperature, using the various electrodes and/or sensorsreferenced above. This can be accomplished using the circuit referencedabove, for example, and can allow device 100 to bemanufactured/configured using fewer components than would otherwise berequired. For example, in device 100 embodiments where conductiveelement 106 is not used, a signal from device 100 can be detected usingpad 200 and transmitted to data acquisition and processing system 250without requiring some sort of return wire or conductor from device 100to data acquisition and processing system 250. Power/current can betransmitted from data acquisition and processing system 250 tooperate/activate circuit module 104, to provide current to excitationelectrodes 126, 128 so that they can generate an electric field within aluminal organ detectable by one or more detection electrodes 122, 124,etc. Data can then be returned back to data acquisition and processingsystem 250 (such as sizing, pressure, temperature, etc., data), eithervia pad 200 or back through device 100, as provided in further detailbelow.

In at least one embodiment of a device 100 of the present disclosure,device 100 is configured with electrodes used for sizing, such as one ormore detection electrodes 122, 124 and one or more excitation electrodes126, 128, and without any other electrodes or sensors. For example, anexemplary device embodiment may comprise two detection electrodes 122,124 positioned in between two excitation electrodes 126, 128, with wires150 connecting the individual electrodes (or pairs of electrodes, asreferenced above), to circuit module 104.

In at least one embodiment of a device 100 of the present disclosure,elongated body 102 and/or conductive element 106 (if present) can beused as a return ground in addition to being used as a signal source(such as providing a signal and/or current from data acquisition andprocessing system 250, whereby the current is used to ultimatelyactivate one or more excitation electrodes 126, 128, for example). Insuch an exemplary embodiment, for example, the circuit could becompleted using device 100 alone, such as by (a) a signal from dataacquisition and processing system 250 through elongated body 102 tocircuit module 104 and ultimately back through elongated body 102 todata acquisition and processing system 250, (b) a signal from dataacquisition and processing system 250 through elongated body 102 tocircuit module 104 and ultimately back through conductive element 106 todata acquisition and processing system 250, (c) a signal from dataacquisition and processing system 250 through conductive element 106 tocircuit module 104 and ultimately back through elongated body 102 todata acquisition and processing system 250, and/or (d) a signal fromconductive element 106 through elongated body 102 to circuit module 104and ultimately back through conductive element 106 to data acquisitionand processing system 250. This bidirectional operation/functionalitywould utilize a circuit module 104 that, in various embodiments, canharvest power/current, facilitate the excitation of excitationelectrodes 126, 128, have amplification capability, handle alternatingand direct current, and/or transmit a signal back through elongated body102, conductive element 106, and/or through the bloodstream to bedetected by pad 200. Use of conductive elements 106 to provide power tothe various sensors/electrodes could be, for example, handled by (a) itsuse as a single conductor in device 100 and the second electrode (suchas excitation electrodes 126, 128 connected to circuit module 104ground) and connected through an electrode (pad 200, for example) on thebody surface to connect back to data acquisition and processing system250 to complete the circuit, or (b) using two conductors in the wire(two conductive elements 106 or one conductive element 106 plus aconductive elongated body 102) to connect power and ground.

Circuit modules 104 of the present disclosure could, for example, bepowered with 0-3V power, which could power conductance circuitry (withincircuit modules 104 and/or in connection with excitation electrodes 126,128) and send data/signal back to data acquisition and processing system250, and if powered with −3-0V, other sensors/circuitry, such aspressure and/or temperature sensors (referred to herein as other sensors130) can be powered and/or pressure and/or temperature data can betransmitted back from circuit modules 104. The variousoperations/functionality could be facilitated by, for example, encodingwhich circuit to power and transmit using a control line (such asconductive element 106) or, for example, a higher voltage pulse on thepower line (elongated body 102 and/or conductive element 106) to togglebetween functions, or even by using different power voltages (such as 3Vand 5V, for example). Furthermore, if an exemplary conductive element106 provides power to circuit module 104, data can be sentbidirectionally in addition to power being sent from data acquisitionand processing system 250 to a sensor/electrode. In at least oneembodiment, a direct current (DC) power signal can be sent along withdata signals.

In various device 100 embodiments of the present disclosure, more thanone circuit module 104 may be used within a single device 100. Forexample, and in a number of device embodiments, excitation of excitationelectrodes 126, 128 and conductance measurements (the voltage acrossdetection electrodes 122, 124) may require two or more circuit modules104, or using one circuit module 104 and a subset of features withinanother circuit module 104, to facilitate the same. For example, all ora subset of the required/necessary functionality of an exemplary circuitmodule 104 could be implemented within a circuit module 104 as a meansof reducing the required number of independent conductors integratedinto the device 100 body. For example, one or more of detectionelectrodes 122, 124 and/or excitation electrodes 126, 128 could becondensed into an additional circuit module 104 (an exemplary integratedcircuit or micromachine assembly).

In at least one embodiment, circuit module 104 would itself operate asan electrode (such as one of the excitation electrodes 126, 128 or oneof the detection electrodes 122, 124), thus reducing the overall needfor one of the electrodes within sizing portion 120. Such an embodimentis shown in FIG. 3 , where circuit module 104 is used in place ofexcitation electrode 128 within sizing portion 120. In otherembodiments, circuit module 104 could replace another electrode.

In at least another embodiment, such as shown in FIG. 4 , at least onedevice 100 embodiment comprises a microassembly 400 having detectionelectrodes 122, 124 thereon/therein, or otherwise configured so thatmicroassembly 400 and at least another electrode would operate asdetection electrodes 122, 124. Such a microassembly 400, when used withexemplary device 100 embodiments of the present disclosure, would allowfor more precision with respect to a length (“L”) between detectionelectrodes 122, 124. In various embodiments, microassemblies 400 and/orcircuit modules 104 of the present disclosure are flexible or inherentlyflexible given their relative size/dimensions. As referenced in one ormore of the patents and/or patent applications listed below, and withrespect to the use of impedance devices 100 and the various electrodesof said devices, conductance data is obtained during operation of saiddevices 100 as generally referenced herein. The governing relationbetween the measured total conductance (G_(T)) and cross-sectional area(CSA) at a particular location within a luminal organ is given by thefollowing:

$\begin{matrix}{G_{T} = {\frac{{CSA} \cdot \alpha}{L} + G_{p}}} & \left\lbrack {{Equation}1} \right\rbrack\end{matrix}$

where L is a constant determined by the distance between detectionelectrodes 122, 124, α is the specific electrical conductivity of thelocal fluid (such as blood), and G_(p) is the parallel conductance. Inview of the same, a precise L is important, and use of a microassembly400 to specifically place electrodes 122, 124 thereon, for example,could be more accurate than otherwise placing separate electrodes alongdevice 100. Such a microassembly 400 could also be positioned in variouslocations between excitation electrodes 126, 128. Various othermicroassembly 400 embodiments can have any number of electrodes/sensorsof the present disclosure positioned thereon, as desired.

Consistent with the foregoing, exemplary devices 100 of the presentdisclosure could use power provided to circuit module 104 from dataacquisition and processing system 250 and leverage the power to twoelectrodes/sensors. For example, power from circuit module 104 to apressure sensor 130 could be leverage to provide power to an excitationelectrode 128, for example, through the same wire 150 or two wires 150connected in series. Additional efficiencies could also be had to reducethe number of electrodes or components by way of sharing power via onewire 150 or two wires 150 connected to two electrodes and/or sensors inseries, or using one component (such as circuit module 104) itself as anelectrode.

An additional embodiment of an exemplary device 100 of the presentdisclosure is shown in FIG. 5 . As shown therein, device 100 is similarto device 100 shown in FIG. 1 , but without wires 150 connecting circuitmodule 104 to the various electrodes/sensors shown therein. In such adevice embodiment, the various electrodes/sensors would operate via awireless connection (via wireless communication) with circuit module104, which is powered, for example, using conductive element 106 oranother power source in various embodiments. In use, device 100, asshown in FIG. 5 , would be operable so that the variouselectrodes/sensors would be able to obtain information/data, asreferenced herein, and circuit module 104 could obtain/access saidinformation/data, wirelessly. FIG. 6 shows an additional embodiment,similar to FIGS. 4 and 5 , whereby a microassembly 400 havingelectrodes/sensors thereon is also in wireless communication withcircuit module 104. Various electrodes/sensors can be positioned on,etched along, or embedded within, exemplary microassemblies 400 and/orcircuit modules 104 of the present disclosure. Said wirelesscommunication, in various embodiments, can be unilateral (such as fromelectrodes/sensors to circuit module 104, or vice versa), or bilateral(such as between electrodes/sensors and circuit module 104). In variousembodiments, circuit module 104 (or other portions of an exemplarydevice 100 of the present disclosure) may comprise (be configured tohave), or have in addition thereto, a wireless communication module 600configured to communicate with various electrodes/sensors of the presentdisclosure. Wireless communication module 600, in various embodiments,can also be powered using conductive element 106 or another powersource. FIG. 6 also shows a balloon 602 positioned around at least partof device 100, so that balloon 602 can be inflated and/or deflated asdesired, such as within a luminal organ, to allow for conductance and/orother measurements to be obtained within balloon 602 using impedance, asgenerally referenced herein. Such an embodiment would allow, forexample, sizing data (cross-sectional area, for example, using theconductance measurements), pressure data, etc., within balloon 602 atvarious degrees of inflation.

FIG. 7 shows another exemplary system 300 of the present disclosure. Asshown in FIG. 7 , an exemplary system 300 may comprise a device 100,which itself comprises a proximal electrical unit 700, a guide wire 740(comprising at least one conductive element 106 therethrough (alsoreferred to as a conductor), and sensor substrate 760 which may comprisean exemplary elongated body 102 of the present disclosure), and a sensorsubstrate 760 at or near a relative distal end 110 of the device 100,with said system 300 comprising one additional element, such as a pad200 (also referred to herein as a patch electrode) and/or a dataacquisition and processing system 250, for example. As shown in FIG. 7 ,proximal electrical unit 700 is proximal to at least part of guide wire740, and sensor substrate 760 is distal to at least part of guide wire740. FIG. 8 shows another exemplary system 300 embodiment, wherebydevice 100 has a first part of guide wire 740 between proximalelectrical unit 700 and sensor substrate 760, and a second part of guidewire 740 distal to sensor substrate 760, whereby the second part ofguide wire 740 has a sizing portion 120 and/or one or more other sensors130 positioned thereon and/or embedded therein, such as a pressuresensor 130. In general, proximal electrical unit 700 can process datasignals 765 (referenced in further detail herein) returning from sensorsubstrate 760 and generally govern operation of proximal electrical unit700 using one or more components therein and/or coupled thereto, suchas, for example, a microprocessor 900 referenced below in connectionwith FIG. 9 . It is to be understood that the data signal 765 travelsfrom the distal portion (sensor substrate 760) to proximal unit 700. Itis further to be understood that the power signal 710 travels from theproximal unit 700 to sensor substrate 760. Transmission of both the datasignal 765 and the power signal 710 is accomplished by the carrier wave1000, referenced in further detail herein, which uses the completeelectrical circuit consisting of guide wire 106, distal unit 760, distalground 768 (or another portion of or coupled to sensor substrate 760, asreferenced in further detail herein), tissue 730, pad 200, wire 202 andthe proximal unit 700.

Exemplary proximal electrical units 700 of the present disclosurecomprise/include at least one power source 702, which may be referred toherein as a power generator and/or a power supply. Power source 702 maycomprise its own direct source of power, such as a battery embodiment ofa power source 702, and/or may itself receive power from a universalserial bus (USB) or other connector 802 (as shown in FIG. 9 , forexample), and/or another power cable supply 804, such as a traditionalelectrical cord configured to be plugged into a traditional power outletwith an appropriate power regulator.

Power from power source 702, USB connector 802, and/or power cablesupply 804, can be provided directly to conductor 106 and/or indirectlyto conductor 106 through one of the aforementionedsources/connectors/supplies and/or one or more other components ofproximal electrical unit 700. Power delivered to conductor 106 fromproximal electrical unit 700 travels through conductor 106 to one ormore elements/components within, upon, and/or embedded within sensorsubstrate 760. As shown in FIG. 7 , for example, power 710 isrepresented by the bold arrow pointing to the right. In a preferredembodiment, power 710 is delivered from power source 702, USB connector802, and/or power cable supply 804 as an alternating current (AC) or anoscillating direct current (DC), such as, for example, a carrier wavetraveling from the proximal unit 700 to distal unit (sensor substrate760) in the form of an alternating current at 200 KHz (alternating at200,000 times per second).

Sensor substrate 760, as shown in FIGS. 7 and 8 , may comprise arelatively small and/or thin substrate, whereby circuit module 104 (alsoreferred to as an integrated circuit) is positioned thereon and/orembedded therein. Sensor substrate 760 may itself be a microassembly 400of the present disclosure, or may be separate from microassembly 400.For example, sensor substrate 760 may comprise or include circuit module104, and microassembly 400 may comprise or include one or more of asizing portion 120 and/or one or more other sensors 130 thereon and/ortherein. As shown in FIGS. 7, 8, and 9 , memory 764 (an exemplarystorage medium of the present disclosure that can be connected tocircuit module 104 and/or other components of sensor substrate 760,whereby memory 964 can store data 765 (as referenced herein) until itcan be transmitted to the proximal electrical unit 700, for example. Invarious embodiments, memory 764 can store various data as noted above,can include instructions and/or software therein to regulate/controlvarious aspects of sensor substrate 700, such as provided in furtherdetail herein.

Elements/components of sensor substrate 760 can be powered using power710 from conductor 106 to achieve several results. One result, forexample, can be to charge a capacitor 762 and/or provide power to adistal power source 766 (shown in FIG. 8 ) within or upon sensorsubstrate 760, so that power from capacitor 762 and/or distal powersource 766 can be used to operate one or more elements within or coupledto sensor substrate 760. Another result can be to directly cause one ormore of sizing portion 120 and/or other sensors 130 to operate (namelythose requiring power to operate), such as to generate an electric fieldusing excitation electrodes 122, 124 of sizing portion 120 (or togenerate an electric field using other elements of sizing portion 120),for example. Yet another result can be to transmit a data signal 765from one or more of sizing portion 120 and/or other sensors 130 back toproximal electrical unit 700 via one or more conductive elements 106and/or wirelessly as noted below. As shown in FIG. 7 , for example, datasignal 765 is represented by the bold arrow pointing to the left. Inother embodiments, data may be transmitted back to proximal electricalunit 700 via or more pads positioned upon the patient, such as, forexample, using a wired or wireless communication module 600 (anexemplary transmitter configured to transmit data to proximal electricalunit 700, for example) within or coupled to sensor substrate 760 totransmit a data signal 765 to proximal electrical unit 700. In at leastone embodiment, and as shown in FIG. 8 , a distal power source 766 maybe used in connection with capacitor 762 such that distal power source766 can provide the necessary power to effectuate one or more of theforegoing, and in various embodiments, can also convert alternatingcurrent (such as provided by power source 702) to direct current so tooperate one or more components of sensor substrate 760. As such, and asreferenced above, power from conductor 106, capacitor 762, and/or distalpower source 766 can be used to effectuate/facilitate one or more of theforegoing results. Capacitors 762, in various embodiments, can be usedby distal power source 766 to power various circuitry within sensorsubstrate 760, especially in situations where power 710 from guide wire740 may be inconsistent and therefore somewhat unreliable, wherebycapacitor 762 and distal power source 766 work in connection with oneanother to deliver consistent and reliable power 710 to portions ofsensor substrate 760.

Data signal 765, as referenced above, originates from componentry upon,within, and/or connected to sensor substrate 760 as shown in FIG. 7 or 8. Data signals 765, referenced in further detail below, can includepressure, temperature, and/or impedance data, and are transmitted backto proximal electrical unit 700 via guide wire 740, in variousembodiments.

General circuits are also shown in FIGS. 7 and 8 . As shown therein, andfor various embodiments, power 710 generally travels from proximalelectrical unit 700 through guide wire 740 and to componentry within,upon, and/or connected to sensor substrate 760. The power circuit isthen completed through the body (such as indicated using ground 768and/or signal 770, in various embodiments) to a pad 200 placed upon thebody, which is then wired back to proximal electrical unit eitherdirectly, such as shown in FIG. 8 , or indirectly, such as shown in FIG.7 . This can be facilitated using one or more components of sensorsubstrate 760 and/or one or more components coupled to sensor substrate760, so that some sort of metallic element is in contact with the bloodand/or tissue of the patient, such as by way of one or more electrodes122, 124, 126, 128, one or more sensors 130, ground 768 (which can be,for example, some sort of antenna or other metallic element), and/oranother metallic component of or coupled to sensor substrate 760. Datasignals 765, as generally referenced herein, can flow in one form oranother (also as described in further detail herein) from componentry ofand/or coupled to sensor substrate 760, through or along guide wire 740to proximal electrical unit 700. The data signal 765 circuit is thencompleted through the body via pad 200 via tissue 730, as shown in FIGS.7 and 8 .

It is noted that the components of system 300 shown in FIGS. 7 and 8 arenot drawn to scale, as, for example, sensor substrate 760 would beconfigured to fit upon, wrap around, and/or be integrated into, part ofconductor 106 so that conductor 106, as part of an exemplary elongatedbody 102 (such as a guide wire, for example), can be inserted into andnavigated through part of a mammalian vasculature as generallyreferenced herein. For example, elongated body 102 (the overall guidewire, having or comprising conductor 106) can be anywhere between 0.010″and 0.050″ in diameter, such as between 0.010″ and 0.030″ in diameter,including, but not limited to, diameters of 0.014″ and 0.035″. Guidewires 740 can be constructed using various metallic and polymericmaterials, and can use one or more conductors 106 as referenced herein.Sensor substrate 760 and/or various sizing portion 120 components and/orsensors 130, would be at or close to such an overall diameter/size so toallow devices 100 and/or parts of systems 300 of the present disclosureto navigate within a vasculature and obtain data as generally referencedherein.

In view of the foregoing, and to complete the overall circuit necessaryto operate such a system 300, power is transmitted from proximalelectrical unit 700 through conductor 106 and into tissue 730 (such asvia proximal ground 704, for example), to operate portions of system 300to obtain data that is then transmitted from sensor substrate 760 toproximal electrical unit 700, so that proximal electrical unit 700obtains feedback (in the form of data) from sensor substrate 760.

Exemplary systems 300 of the present disclosure may also have additionalcomponentry such as shown in FIG. 9 . As shown in FIG. 9 , for example,one or more exemplary systems 300 of the present disclosure may comprisea device 100 comprising a proximal electrical unit 700, a guide wire740, and a sensor substrate 760. Proximal electrical unit 700, asdescribed herein in various embodiments, may comprise/be a handle orother configuration and include a power source 702 and optionally mayinclude a USB or other connector 802 and/or a power cable supply 804 (asshown in FIG. 8 ). USB or other connector 802 can be used as a source ofpower, as previously described herein, and/or used to transmit data(such as data signal 765) outside of proximal electrical unit 700, suchas via wired or wireless connection to a computer (not shown) connectedto proximal electrical unit 700. A microprocessor 900, orfunctionally-equivalent componentry, may be present within or as part ofproximal electrical unit 700, configured for several different types ofoperation, such as, for example, controlling power 710 and/or datasignal 765 flow through portions of proximal electrical unit 700,accessing optional memory 902 (an exemplary storage medium of thepresent disclosure) in communication with microprocessor 900 so tocontrol one or more aspects of device 100 such as the foregoing, and thelike. FIG. 9 also shows a receiver 904, in communication with guide wire740, which operates to receive one or more data signals 765 from guidewire 740, whereby said one or more data signals 765 can beprovided/displayed to a user of device 100, accessed by microprocessor900 to control future power 710, to store said one or more data signals765 within memory 902, and/or to compare the one or more data signals765 to each other, to other data signals 765 within memory 902, and/orto other data stored within memory 902, such as calibrationinformation/data in connection with various sensor(s) 130 and/or sizingportion(s) 120. Data signals 765 and/or other data can be stored withinmemory 902 and outside of proximal electrical unit 700 so that if someor all of a connection to proximal electrical unit 700 is lost duringoperation, such as via USB or other connector 802, device 100 can stilloperate using data within memory 902 accessible using microprocessor900. Memory 902, in various embodiments, can store various data as notedabove, can include instructions and/or software therein toregulate/control various aspects of proximal electrical unit 700,interface with a data acquisition and processing system 250, etc.

Proximal electrical units 700, as generally referenced herein, can formand/or be located in a relative handle portion of device 100, asreferenced above, which can be held by a medical professional using saiddevice 100. In general, proximal electrical units 700 of the presentdisclosure can generate a carrier wave 1000, referenced herein infurther detail and shown in FIG. 10 , for example), that can be sent tosensor substrate 760 over the circuit formed by guide wire 740 andtissue 130. Exemplary carrier waves 1000 can provide power 710 necessaryto operate elements within sensor substrate 760, and can be modulated bysensor substrate 760 to send data signals 765, which are recovered byproximal electrical unit 700 by the demodulation of the carrier wave1000. Carrier waves 1000 can also be interrupted, as referenced infurther detail herein, to indicate to the sensor substrate 760 that itis safe to obtain measurements. Proximal electrical units 700 of thepresent disclosure can also relay data signals 765 obtained from sensorsubstrate 760 to a data acquisition and processing system 250, such asshown in FIG. 7 , for further processing and/or display purposes, whichcan be facilitated using USB, RS-232, Wi-Fi, Bluetooth, Zigby, and/orother known or developed wired and/or wireless means of transmittingdata.

In various embodiments, data signals 765 are modulated when sent fromthe distal part of device (sensor substrate 760) through guide wire 740to proximal electrical unit 700. In at least some embodiments, receiver904 is configured to demodulate said data signals 765 so that thedemodulated data signals 765 can be acted upon (received, processed,etc.) by microprocessor 900.

The distal part of device 100 (including sensor substrate 760) can havesome or all of the componentry/features shown in FIG. 9 . For example,and as shown therein, an exemplary sensor substrate 760 of the presentdisclosure may comprise a circuit module 104 (also referred to herein asan integrated circuit), a wired or wireless communication module 600 (anexemplary transmitter, configured to transmit data signals 765 fromsensor substrate 760 to guide wire 740 so that data signals 765 can beprovided to proximal electrical unit 700), a pressure sensor (anexemplary sensor 130), and a sizing portion 120 (comprising electrodes122, 124, 126, 128, for example). Various wires or traces 980 may bepresent within proximal electrical unit 700 and/or sensor substrate 760,used to connect any number of components to one another for operation asgenerally referenced herein. Exemplary wires or traces 980 are shown inFIG. 9 .

An exemplary pressure sensor (sensor 130) of the present disclosure mayhave a diaphragm 910 that bends in response to changes in pressurethereto. For example, the three left pointing arrows in FIG. 9 areindicative of a force against diaphragm 910 of sensor 130 whereby, forexample, an outer portion of diaphragm 910 is elongated and an innerside of diaphragm 910 is compressed. An exemplary bridge 912, connectedto sensor 910 directly or via one or more wires or traces 980, canmeasure extremely small differences between the inner and outer sides ofdiaphragm 910 (thereby detecting very small signals from sensor 130),and via one or more amplifiers 914 connected thereto, can share one ormore data signals 765 from sensor 130 to multiplexer 920 and/or directlyto a transmitter (wired or wireless communication module 600), which canthen send data signals 765 to proximal electrical unit 700 through guidewire 740 and/or wirelessly (such as by using one or more wirelesssignals, radio frequency signals/waves, Bluetooth, etc.) when a wirelesstransmitter is used. Amplifiers 914, as shown in FIG. 9 , can amplifydata signals 765 from bridge 912 so to increase the overall strength ofdata signals 765. As shown in FIG. 9 , for example, bridge 912 canactually receive two pieces of data from the pressure sensor (sensor130), with one being a difference between the inner and outer diaphragm910 changes, relating solely to a change in pressure, and the otherbeing a sum of said changes, which utilizes a temperature component aswell (as a pressure sensor 130, for example, can compensate fortemperature changes). In view of the same, amplifiers 914 can amplifyboth types of data signals 765 (pressure, indicated as “P” in FIG. 9 ,and temperature, indicated as “T” in FIG. 9 ). Similarly, an amplifiercan amplify impedance (indicated as “Z” in FIG. 9 ) data signals 765from sizing portion 120, as shown in FIG. 9 , so to increase theiroverall strength prior to getting to a multiplexer 920.

Exemplary pressure sensor(s) 130 of the present disclosure can be placednear the distal tip/end 110 of the medical device 100 and is/aredesigned to measure the pressure of the blood. Although many embodimentsare possible, at least one embodiment consists of a pair of straingauges mounted on the opposite sides of a flexible substrate (thediaphragm 910 mentioned above), which bends and changes it curvaturewhen the force applied on one side changes relative to the opposingside. When the two aforementioned strain-gauges are configured as adifferential pair, the signal that is measured from a full or halfWheatstone bridge is proportional to the normal force that is applied onthe pressure sensor 130. However, when the strain gauges are configuredas resistors in series, then the signal that is produced is proportionalto the temperature of the blood, as generally referenced above.

A multiplexer 920, shown in FIG. 9 , can obtain data signals 765 fromvarious inputs, such as sensor(s) 130 and/or sizing portion 120, andforward and/or process one data signal 765 at a time, as desired. Forexample, multiplexer 920, as shown in the figure, can obtain pressureand temperature data signals 765 from sensor 130 (configured as apressure sensor), as well as sizing (impedance) data signals 765 fromsizing portion 120. Multiplexer 920, after receiving said data signals765, can share them one at a time, such as, for example, first sharing adata signal 765 from or relating to sizing portion 120, and then sharinga data signal 765 from or relating to sensor 130. An analog-to-digitalconverter 922, as shown in FIG. 9 , can be connected to (incommunication with) multiplexer 920, and operate to convert analog datasignals 765 from sizing portion 120 and/or sensor(s) 130 to digitalsignals 765, which are then forwarded to circuit module 104 (such as anintegrated circuit and/or microprocessor) and transmitted back toproximal electrical unit 700 via wired or wireless communication module600 (an exemplary transmitter of the present disclosure). In variousembodiments, wired or wireless communication module 600 is itself anelectrode (or configured as an electrode), such as a coil, one ofelectrodes 122, 124, 126, or 128, or a separate electrode, so that datasignals 765 can properly be transmitted back to proximal electrical unit700.

Exemplary sensor substrates 760 may utilize one or more switches duringoperation. For example, a first switch 930 may be used to electricallyconnect (via power 710 and/or data signal(s) 765) guide wire 740, wiredor wireless communication module 600, and distal power source 766. Asecond switch 932 may be used to electrically connect (via power 710and/or data signal(s) 765) distal power source 766 with tissue 730, asshown in FIG. 9 . FIG. 13 shows the event generation 1300 that isgoverned by the distal unit (sensor substrate 760), which runs as aslave to the proximal electrical unit 700. Briefly, and as shown in FIG.13 , event generation 1300 is started at start step 1302, and sensorsubstrate 760 is initially effectively connected to guide wire 740 andtissue 130, by being in the ISOLATE OFF state (at isolate off state1304), which is achieved by the closure of the switches S1 (first switch930) and S2 (second switch 932), as shown in FIG. 9 . At that time, thecapacitors 762 referenced herein are charged to provide the power thatwill be necessary to operate the distal circuitry (within sensorsubstrate 760) when the carrier wave 1000 will be interrupted. Distalunit (sensor substrate 760) continues to monitor the power (via is poweron step 1306), and when the power is off, that is when the carrier wave1000 is interrupted by proximal electrical unit 700, sensor substrate760 enters into the measurement mode (measurement step 1310). First thedistal tip electronics (components within sensor substrate 760) areisolated from the tissue 130, as indicated by the ISOLATE ON state inFIG. 9 (isolate on state 1308), which is achieved by the opening of theswitches S1 and S2 (first switch 930 and second switch 932,respectively), as shown in FIG. 9 . Subsequently, impedance, pressureand/or temperature measurements can be made, and the electricalisolation of the distal tip electronics is terminated (via isolate offstate 1312). At this point, the distal tip circuitry (of sensorsubstrate 760) waits for the restoration of the carrier wave by theproximal circuitry (of proximal electrical unit 700) before attemptingto send the resulting measurements (data signals 765) back to proximalelectrical unit 700 (via data transmission step 1318), which is done bythe modulation of the carrier wave 1000. Once the power is back on (viais power on step 1314), a brief delay (delay state 1316) can precededata transmission step 1318. Modulation scheme can be chosen among manythat are available, such as amplitude modulation, pulse positionmodulation, pulse width modulation, and so on. Similarly, coding of thedata (data signal 765) can be done by choosing from a large selection oftechniques that are available. For example, Amplitude modulation andManchester Coding may be preferred as they do generate signals with zerooffset, which is important for data signals 765 sent over tissue 130 toprevent adverse effects and unintentional stimulation. Opening andclosing of switches 930, 932 are discussed in further detail herein.

Various additional wires or traces 980 may be present within proximalelectrical unit 700 and/or sensor substrate 760, used to connect anynumber of components to one another for operation as generallyreferenced herein. Exemplary wires or traces 980 are shown in FIG. 9 .Novel operation of exemplary devices 100 and/or systems 300 of thepresent disclosure can be described in view of the exemplary carrierwave timing diagram shown in FIG. 10 . As shown therein, a singlecarrier wave 1000 is used along with the overall power signal from theproximal electrical unit to direct operation of various aspects ofdevice 100 and/or systems 300. For example, and as shown in FIG. 10 , anexemplary carrier wave 1000 has a measurement portion 1002, wherebymeasurements using device 100 are obtained within a mammalianvasculature, and a charge portion 1004, whereby elements within sensorsubstrate 760 are charged using power 710 from conductor 106 (or,phrased differently, whereby power 710 is turned back on by the proximalelectrical unit 700). In measurement portion 1002, for example,components of the sensor substrate 760 identify that no power 710 isflowing thereto from guide wire 740, which can act as a trigger toobtain one or more measurements (using sensor(s) 130 and/or sizingportion(s) 120, without electrical interference due to said power 710flow. Carrier waves 1000 of the present disclosure also include a datatransmission portion 1006, whereby data obtained using device 100 istransmitted back to proximal electrical unit 700, and a stand-by portion1008, where no data is obtained or transmitted, and which acts as atrigger for device 100 and/or system 300 to obtain additional data.During measurement portion 1002, power 710 is not provided from theproximal electrical unit 700 to the sensor substrate 760, which can actas a trigger for one or more components of sensor substrate 760 toobtain one or more pressure, temperature, and/or impedance measurements.During an exemplary data transmission portion 1006, components of thesensor substrate 760 may vary the overall amount of current/power it isdraining, and proximal electrical unit 700 can monitor said power drain.Sensor substrate 760 can intentionally alter an amount of power it isdraining (such as relatively less power or relatively more power,considered as a binary 0 or 1). During stand-by portion 1008, power 710can be used to charge capacitor 762 as well, in various embodiments.

In general, and as referenced herein, exemplary devices 100 of thepresent disclosure are operable and/or configured to send power 710 andmultiple data signals 765 over the same guide wire 740. Sizing portion120 and/or sensor(s) 130 of the present application interfaceelectrically, as various devices 100 and send current (power 710) andobtain various measurements (resulting in data signals 765) at the sametime or very close in time to one another. Using a single core (a signalconductive element 106 or conductor), power 710 and data signals 765 canbe sent over the same core, with the overall power and data circuitscompleted by the body (tissue 130). In view of the same, devices 100 ofthe present disclosure can be consider as using multiple channels, invarious embodiments, of data signals 765 and power 710.

FIG. 11 shows steps of an exemplary event generation 1100 from anexemplary proximal electrical unit 700 of the present disclosure. Asshown therein, an exemplary device 100 can start operation (using startstep 1102) and power transmission can be turned off (using power offstep 1104), whereby measurements can be obtained using portions ofdevice 100 and/or system 300, such as impedance, pressure, and/ortemperature measurements, either at power off step 1104 or delay step1106, which is included so to allow time for inherent tissue capacitanceto go down to allow for cleaner measurements. Said measurements would beobtained when no power is being transmitted through conductor 106 tosensor substrate 760, for example, so to minimize the potential negativefeedback from such a transmission during data acquisition, allowing fora cleaner (and therefore more accurate) data acquisition process. Powercan then be turned on (using power on step 1108) to provide power tosensor substrate 706 so that, for example, wireless communication module600 within sensor substrate 760 can send the data signal 765 to proximalelectrical unit 700, for example. Another delay step 1110 follows thepower on step 1108, so that tissue capacitance due to power on step 1108can be reduced and allow for a cleaner transmission of data acquiredusing device 100 and/or system 300 within data receipt step 1112. Anadditional delay step 1114 may follow data receipt step 1112, with thefinal step in the event generation 1100 shown in FIG. 11 being to sendthe data signal 765 to either the proximal electrical unit 700 and/or toa data acquisition and processing system 250 at data transmission step1116. Once the data has been transmitted at data transmission step 1116,the process can repeat itself as shown in the Figure. It is noted thatdelay steps 1106, 1110, and 1114 are optional, but are recommended invarious embodiments so to allow for the cleanest operation of device 100and/or system 300.

Device 100 and/or system 300 embodiments using a single conductor (asingle conductive element 106), as referenced herein, can use mammaliantissue 130 to complete the overall power and/or data circuits. Saiddevices 100 would have preferred flexibility and/or steerability, asguide wires 740 of such a small size as referenced herein would besomewhat compromised should more than one core (conductive element 106)be used. However, the present disclosure does also include disclosure ofdevices 100 having two or more cores (conductors/conductive elements106), such as shown in FIG. 12 , so that the overall circuit can becompleted within device 100. For example, and as shown in FIG. 12 ,device 100 can comprise a proximal electrical unit 700, a guide wire 740having two conductive elements 106, and a distal sensor substrate 760,each having various features and/or elements as referenced herein. Power710 and data signals 765 (not shown in FIG. 12 , but shown in otherfigures herein) can be transmitted over/through the loop created byproximal electrical unit 700, a first conductive element 106, sensorsubstrate 760, and a second conductive element 106, as shown in FIG. 12.

At least one issue that must be addressed by the distal circuitry(within sensor substrate 760) is the existence of a common electricalpath between the power circuitry and impedance that is being measured,for example. The principles of electrical impedance measurements usingthe quadripolar (tetrapolar) impedance technique (two excitationelectrodes 126, 128 used to generate an electric field 1400 detectableusing two detection electrodes 122, 124 positioned within the twoexcitation electrodes 126, 128, as generally referenced herein), areillustrated in FIGS. 14 and 15 . As identified within FIGS. 16 and 17 ,when the power is supplied over the same tissue that the impedance ismeasured from, a residual shunt path remains in the measurement path,making the results of the impedance measurement inaccurate. To solvethis issue, measurements can be made only during the part of the cyclewhen the proximal circuitry (within proximal electrical unit 700) turnsoff the carrier wave 1000, and then the distal circuitry (within sensorsubstrate 760) turns on the isolation by opening first switch 930 andsecond switch 932 as shown in FIG. 9 . In various embodiments of thepresent disclosure, electrodes 122, 124, 126, 128 are formed as ringsaround the distal portion 110 of device 100. These electrodes areusually 1 mm wide bands and are constructed from a platinum-iridiumalloy, but different sizing and different materials are included withinthe present disclosure. Spacing between the individual electrodes 122,124, 126, 128 is in the range of 0.5 to 10 mm.

FIG. 18 shows a distal portion (sensor substrate 760) of an exemplarydevice 100 of the present disclosure, having two capacitors 762, fourelectrodes 122, 124, 126, 128, a pressure sensor (exemplary sensor 130),and an integrated circuit (circuit module 104), connected as shown usingvarious wires or traces 980, configured for operation as generallyreferenced herein. FIG. 19 shows exemplary power 710 and data signal 765flow directions using various devices 100 of the present disclosure,whereby, for example, power 710 flows from proximal electrical unit 700through guide wire 740 to sensor substrate 760, to pad 200 (via one ormore mechanisms or methods noted above, such as by contact of a metalliccomponent of or coupled to sensor substrate 760 so to continue thegeneral circuit/loop) and back to proximal electrical unit 700 via padwire 202 and/or coupler 210, and whereby, for example, data signals 765flow from sensor substrate 760 through guide wire 740 to proximalelectrical unit 700 and back to sensor substrate 760 as shown therein tocomplete the loop/circuit. As shown in FIGS. 7, 8, and 19 , for example,power 710 is shown as generally moving in one direction and data signals765 are generally shown as moving in another direction. Althoughelectrons (from oscillating alternating current (AC) or pulse directcurrent (DC), as desired) move in both directions along the circuit, thearrows shown in FIGS. 7, 8, and 19 are included to depict, for example,the overall flow of power 710 from power source 702 to circuit module104 of sensor substrate 760, for example, and the overall flow of datasignals 765 from circuit module 104 back to proximal electrical unit700. With respect to power 710 and data signal flow 765, the overallcircuit is completed using two conductors, at least one being one or afirst conductive element 106 of guide wire 740, and the other beingcompleted through the body back to pad 202 and pad wire 202, forexample, as referenced herein.

As generally referenced herein, various devices 100 and systems 300 ofthe present disclosure are useful to obtain measurements within amammalian vasculature, such as to identify locations of stenoticregions, for example, and to obtain cross-sectional area measurementsusing impedance to potentially aid in the pre-selection of varioustherapeutic devices. Impedance, blood pressure, and/or temperature canbe obtained using various transvascular devices 100 and/or systems 300of the present disclosure.

As generally referenced herein, various devices 100 of the presentdisclosure may comprise a sizing portion 120 having various electrodes,such as electrodes 122, 124, 126, and/or 128 referenced herein,including those four electrodes, additional electrodes, and fewerelectrodes. Device 100 embodiments may comprise one or more of a sizingportion 120, a sensor 130 configured to obtain temperature measurements(such as a thermistor or thermocouple), and/or a sensor 130 configuredto obtain pressure measurements (such as a pressure sensor). Othersensors 130 used in the medical arts may be incorporated into variousdevice 100 and/or system 300 embodiments, as applicable.

Example

Two custom circuits were built to test an exemplary embodiment of thepresent disclosure. One of the circuits is referred to as the proximalcircuitry and performs the functions of a proximal electrical unit 700such as shown in FIG. 7 including the generation of the carrier wave,transmission of the power, reception of the data from the distalcircuitry and communication with an external computer. The operations ofproximal electrical unit 700 in this example are governed by an ArduinoUno micro-controller board running a program that was written inProcessing Language. This same board did communicate with an externalcomputer using a USB connection 802. Power was obtained from a 9 Voltprimary battery. The overall current draw from the battery wasapproximately 80 milli-Amperes.

The second circuitry is referred to as the distal circuitry and performsthe functions of the elements within or upon sensor substrate 760 asshown in FIG. 7 , for example, including the power recovery from thecarrier wave, the data transmission by the amplitude modulation (AM) ofthe carrier wave using the Manchester coding, data collection using theon board sensors including the pressure sensor, temperature sensor (bothexemplary sensors 130) and the quadripolar/tetrapolar impedance sensor(an exemplary sizing portion 120). The pressure that was used is adifferential strain gauge sensor which also served as temperaturesensor. The operation of the distal circuitry was governed by a PIC16F690 microcontroller running a program that was written in thelanguage C++.

The carrier wave that is used was a 200 KHz square wave that wasgenerated by the proximal circuitry. Data transmission was done at 9,600baud (bits per second) using data packages that are 14 bits long, whichis described below and also illustrated in FIG. 20 :

Bit 01: Start Bit (Always “1”)

Bit 02 & 03: Channel Number (00: Reserved, 01: Impedance, 02: Pressure,03: Temp)

Bit 04-13: 10 bit data

Bit 14: Even Parity bit

Use of Manchester code required the data transmission to be done using alogic level sequence of a low level followed by a high level for thetransmission of a data value of “1” and a logic level sequence of a highlevel followed by a low level for the transmission of a data value of“0”, as illustrated in FIG. 21 .

Electrical current intensity of the carrier wave was kept below 1milli-Amperes at all times. The electrical circuit that is necessary tocarry the wave was formed using a solid wire and the tissue as shown inFIG. 22 . Connections to the tissue were made using a pair of patchelectrodes.

During the acute in vivo study, a male rabbit was kept anesthetizedusing inhaled gas throughout the procedure. Vascular access was gainedto the jugular and femoral veins via routine cut-down and with theplacement of introducers at both sites. A 0.035″ LumenRECON guide-wirewas placed into the vein from the jugular entry point, and it wasadvanced into the superior vena cava. Radio-opaque dye that wasintroduced into the venous system was used to capture a venogram of thevessel which was later used to estimate the diameter of the vein atvarious locations while the guide-wire was being repositioned at fourdifferent positions. Finally, a 4 French Merit KA2 catheter was used torelease room temperature normal saline (0.9% NaCl) from a distance of 19mm from the center of the impedance electrodes numbered 2 and 3(exemplary detection electrodes 122, 124 of an exemplary sizing portion120).

The following observations were made during the study:

-   -   1. When the proximal and distal circuits were connected using a        solid wire+animal tissue path, the distal circuit was powered,        as demonstrated by the “return signal receive indicator” that is        present on the proximal circuitry.    -   2. When the micro-processor (an exemplary circuit module 104)        residing in the distal circuitry was programmed to send fixed        data values, those values were reliably received by the proximal        circuitry, sent to the computer via the USB port and displayed        on the computer screen, indicating that reliable data        transmission over the tissue can be accomplished.    -   3. When the micro-processor residing in the distal circuitry was        programmed to send the data from the transducers, pressure        sensor data was received, and changes in the pressure data was        observed when a manual force was applied to the pressure sensor,        indicating that the pressure sensor interface is functional.    -   4. When the guide-wire is positioned at different locations in        the vein of the rabbit as shown in FIG. 23 , it was possible to        measure the in vivo electrical impedance using the quadripolar        impedance sensor (an exemplary sizing portion 120) that is on        the distal circuitry. During the study, four different positions        were tried, as shown in Table 1 below.

TABLE 1 Quadripolar impedance data collected during the in vivo studyDiameter Cross Sectional Area (V₂ − V₃) × 5 Conductance (mm) (mm²)(volts) (μ-Siemens) 6.56 33.8 3.66 683.06 9.98 78.23 3.38 739.64 10.6188.41 3.19 783.70 11.1 96.77 3.05 819.67

Data shown in tabular format in Table 1 and in graphical format in FIG.24 show the predicted relationship between the conductance and the crosssectional area of the blood vessel.

When a bolus amount of normal saline (0.9% NaCl) at room temperature wasinjected using a 4 French Merit KA2 catheter into the vessel at aposition that is 19 mm away from the center of the electrodes 2 and 3 ofthe guide wire, a transient response in the voltage, as shown in FIG. 25was observed. Since normal saline has a higher conductivity compared toblood, the voltage drop observed between the electrodes 2 and 3 wasreduced, as expected, during the passage of the saline over the distalportion of the catheter.

Portions of an exemplary device 100 embodiment of the present disclosureare shown in the exploded component view shown in FIG. 26 . As showntherein, conductive element (conductor 106) has at least three segments,namely a proximal segment 2600, a distal segment 2602, and an innersegment 2604, whereby the proximal segment 2600 and the distal segment2602 are each configured to couple to opposite ends of inner segment2604. Inner segment 2604, as shown in FIG. 26 , is configured to receivea corresponding wrap 2650 thereon, wherein wrap 2650 is configured to bewrapped around most or all of inner segment 2604. Proximal segment 2600can be connected/coupled to inner segment 2604, and distal segment 2602can also be connected/coupled to inner segment 2604, using variousconnections and/or means, such as, for example, using one or more of anadhesive, weld (such as solder and/or using additional metal), melt(such as melting plastic), twisting, friction, etc. In at least oneembodiment of a device 100 of the present disclosure, and as shown inFIG. 26 , proximal segment 2600 and distal segment 2602 each have a tab2606 at their end that will connect/couple to inner segment 2604, andinner segment 2604 has a pocket 2608 defined therein at each end toreceive tabs 2606 to connect the same.

A component housing 2675, as shown in FIG. 26 , is configured to receivevarious components of exemplary devices 100 of the present disclosure,such as a pressure sensor (an exemplary sensor 130), a circuit module104 (also referred to herein as an integrated circuit or ASIC), and acapacitor 762. A transfer circuit 2680, as shown in FIG. 26 , cancomprise various wires or traces 980 that are configured to touch orengage other wires or traces 980 formed on other parts of device 100,such as on or included within wrap 2650 and/or inner segment 2604. Forexample, various wires or traces 980 can be used to connect one or morecomponents within component housing 2675 and/or be used to provide theconnections of transfer circuit 2680 so to allow the components withincomponent housing 2675 to electrically communicate with other portionsof device 100, such as, for example, other wires or traces 980,components of a sizing portion 120, a pressure sensor (exemplary sensor130), conductive element (or conductor) 104, and the various partsthereof, such as proximal segment 2600 and/or distal segment 2602.

During overall assembly of an exemplary device 100 embodiment as shownin FIGS. 26 and 27 , components intended to be positioned withincomponent housing 2675, such as the pressure sensor (sensor 130),circuit module 104, and capacitor 762, are positioned within componenthousing 2675. One or more component housing apertures 2676 is/aredefined within component housing 2675 so to allow blood, for example, tocontact pressure sensor (sensor 130) to permit pressure readings whendevice 100 is in use to obtain the same. Transfer circuit 2680 caneither contact other wires or traces 980 of component housing 2675 thatare configured to contact other wires or traces 980 or components ofdevice 100, or transfer circuit 2680 can be exposed through a transfercircuit aperture 2678, as shown in FIGS. 30A and 30C, defined withincomponent housing 2675 so to expose the same.

Component housing 2675, with components therein, can be positionedwithin inner segment 2604, so that one or more inner segment apertures2610 defined within inner segment can correspond/align with one or morecomponent housing apertures 2676 defined within component housing 2675.Wrap 2650 can be wrapped around inner segment 2604, and proximal segment2600 and distal segment 2602 can be connected to inner segment 2604 tocomplete construction of the device 100 as shown in FIG. 26 . Wrapapertures 2655, as shown in FIG. 26 , can correspond/align with the oneor more inner segment apertures 2610 and the one or more componenthousing apertures 2676. As shown therein, when wrap 2650 is positionedaround inner segment 2604, various components thereof (such aselectrodes 122, 124, 126, 128 (shown in FIGS. 26 and/or FIG. 28C), adistal conductor pad 2620, a proximal conductor pad 2700 (as shown inFIGS. 29D and 29E), and/or various wires or traces 980) can contactvarious portions of inner segment 2604, such as wires or traces 980,distal conductor contact 2612, one or more electrode contacts 2614,and/or a proximal conductor contact 2616.

FIG. 27 shows a perspective view of a portion of the device 100 shown inFIG. 27 that is generally assembled but for positioning of the wrap 2650around inner portion 2604. As shown in FIG. 27 , a pressure sensor(sensor 130), circuit module 140, and capacitor 762 are positionedinside device 100, with a partial cut-away view provided in FIG. 27 tosee said components therein. FIG. 27 also shows a distal portion of acatheter 2750 configured for delivery over device 100 within a mammalianvasculature, whereby an optional fluid, such as saline, can be deliveredtherethrough so that a bolus of the fluid can pass over one or moresizing portions 120 and/or sensors 130 and be detected thereby, asgenerally referenced herein.

FIG. 28A shows a cross-sectional view of a portion of an exemplarydevice 100 of the present disclosure as shown along cross-section B-B inFIG. 28C. As shown therein, device 100, with wrap 2650 positionedthereon, includes a pressure sensor (sensor 130) within a componenthousing 2675 having one or more component housing apertures 2676 definedtherein, and a transfer circuit 2680. FIG. 28B shows a cross-sectionalview along cross section A-B shown in FIG. 28D, whereby variouscomponents are shown inside of device 100 with wrap 2650 positionedthereon. FIGS. 28C and 28D show side views, rotated 90° from oneanother, of distal portions of an exemplary device 100 of the presentdisclosure with a wrap 2650 positioned thereon, whereby electrodes 122,124, 126, 128 and distal conductor pad 2620 are shown thereon.

FIG. 29A shows a perspective view of a portion of an exemplary device100 for the present disclosure having a wrap 2650 positioned thereon,whereby electrodes 122, 124, 126, 128, distal conductor pad 2620, andproximal conductor pad 2700 are shown thereon. Such a view does not showthe most distal portion and the most proximal portion of device 100.FIG. 29B shows a perspective view of an exemplary wrap 2650 having wrapapertures 2650 defined therein.

FIG. 29C is a magnified view of circular area A of wrap 2650 shown inFIG. 29D. As shown therein, various wires or traces 980 can terminate atone or more wire or trace termination points 982, whereby terminationpoints 982 are configured to contact other componentry of device 100,such as one or more of electrodes 122, 124, 126, 128, distal conductorpad 2620, proximal conductor pad 2700, distal conductor contact 2612,electrode contact(s) 2614, and/or proximal conductor contact 2616, forexample. An exemplary wrap 2650, as shown in the front and back (or topand bottom) views shown in FIGS. 29D and 29E, includes electrodes 122,124, 126, 128, distal conductor pad 2620, proximal conductor pad 2700,various wires or traces 980, and one or more wrap apertures 2655 definedtherein. Various wraps 2650 of the present disclosure can be connectedto portions of device 100 (such as inner segment 2604 or a unitary core(conductive element or conductor 106) by way of, for example, one ormore of adhesives, heat-shrinking, and/or mechanical connections.

FIGS. 30A-30E show views of portions of an exemplary component housing2675 with various components therein. FIG. 30A shows a cut-away view ofpart of a component housing 2675 with a pressure sensor (sensor 130) andtransfer circuit 2680 therein, with transfer circuit extending fromwithin component housing 2675 via a transfer circuit aperture 2678defined within component housing 2675. FIG. 30B shows a perspective viewof half of a component housing 2675 with a pressure sensor (sensor 130),circuit module 104, and capacitor 762 therein, with a transfer circuit2680 connected to one or more of said components, such as by way ofwires or traces 980 shown in FIG. 30E. FIG. 30D is a cross-sectionalview of part of the component housing 2675 shown in FIG. 30C, withvarious components therein. FIG. 30E shows a cross-sectional view of acomponent housing 2675 showing the components shown in FIG. 30B, notingthat an exemplary transfer circuit 2680 of the present disclosure hasone or more traces or wires 980 to facilitate electrical connection toother components as generally referenced herein.

In general, coronary guide wires need to be limited to an outer diameterof 0.014″ so to be small enough to navigate to distal regions ofcoronary arteries and to accommodate coronary catheters which havelumens in that general size range. The guide wire cores therefore mustbe made of high modulus materials which take up as much of the 0.014″cross section as possible, so they are as stiff as possible fornavigation purposes, and so they can enable delivery of the coronarycatheters into tortuous anatomy.

Pressure sensing guide wires generally cannot be made with high modulusmetals over most of the core cross section because they need toaccommodate three (3) electrical conductors from the proximal to distalend of the device, somewhere within that cross section. As referencedherein, various device 100 embodiments of the present disclosure usefour (4) electrodes (electrodes 122, 124, 126, and 128) to obtain sizingdata, along with the use of a pressure sensor (sensor 130), andtherefore a traditional device using these components would generallyrequire at least seven (7) total conductors. Other sensors, such as atemperature sensor, would increase that number of conductors.

To be able to generate a device 100 configured as a guide wire having anouter diameter of 0.014″ or less, useful to obtain sizing data andpressure data, Applicant's present disclosure includes variousconfigurations of devices 100 using only one core (conductive element orconductor 104), whereby the combination of the ASIC (an exemplarycircuit module 104) and a pad 200 (return patch) would allow for only asingle core to be needed to operate several types of sensors, allowingfor such devices 100 to be delivered similar to standard workhorse guidewires on the market today.

As referenced herein, exemplary proximal electrical units 700 of thepresent disclosure contain componentry that can perform variousfunctions including, but not limited to:

-   -   a) powering of the distal circuitry (elements within, part of,        and/or coupled to sensor substrate 760), such as by way of        providing power from power source 702 to and through conductive        element 106 to sensor substrate 760; and/or    -   b) communicating with the distal circuitry to initiate the start        of each sensory measurement phase, such as referenced in FIGS.        10, 11, and 13 and as generally referenced herein; and/or    -   c) receiving data signal(s) 765 from the distal circuitry        (within, part of, and/or coupled to sensor substrate 760) which        contains diagnostic data as well as the data from the sensors        (such as sizing portion 120 and/or sensors 130); and/or    -   d) interpreting the data 765 coming from the sensors, such as        correcting for non-linearities and offset errors in the sensory        data, by way of using a microprocessor 900, for example; and/or    -   e) storing device 100 specific information, such as sensor gain,        sensor offset and device serial number, such as within memory        902 (an exemplary storage medium of the present disclosure);        and/or    -   f) communicating the resulting data to other devices, such as        computers for visualization by medical professionals; and/or    -   g) providing data that can be used for brand protection.

Functions listed above can be accomplished using a combination of analogand digital circuitry, such as a micro-controller (microprocessor 900)running a program which governs the operations of the entire proximalcircuitry (within proximal electrical unit 700). Analog circuitry can beprimarily responsible for the first three functions listed above, whiledigital circuitry can support the last four items on the list, forexample. In an exemplary preferred embodiment, the proximal circuitry(proximal electrical unit 700) is housed within the handle portion ofthe guide wire (device 100), noting that the present disclosure alsosupports implementations where some part of the proximal circuitry, suchas the analog circuitry, is placed within the handle while the digitalcircuitry is kept in the console, such as shown in an interpretation ofFIG. 7 whereby element 700 (proximal electrical unit) comprises thehandle and data acquisition and processing system 250 isconnected/coupled to handle 700, with data acquisition and processingsystem 250 and handle 700 each including one or more component asreferenced herein in connection with the same, such as, for example,power source 702, microprocessor 900, and/or memory 902. While theformer option may provide for a simpler design (such as by requiringless additional componentry to operate device 100), the latter optionsallow a lower cost built by reducing the part count (overall componentryin the consumable/disposable portion of the medical device 100. Forexample, if an exemplary device 100 of the present disclosure isintended for one-time use (such as, for example, use with one patient),some or all proximal electrical unit 700 components could be includedwithin data acquisition and processing system 250 versus a handleportion of device 100. In device embodiments 100 of the presentdisclosure whereby circuitry/componentry is included within proximalelectrical unit 700 configured as a device 100 handle, housing aroundthe proximal circuitry (an exemplary embodiment of proximal electricalunit 700) can keep it fluid impermeable and allow the entire medicaldevice 100, including the proximal handle (an exemplary proximalelectrical unit 700), to be sterilized using traditional methods, suchas ethylene oxide sterilization.

In addition, and as generally referenced herein, an exemplary carrierwave 1000 of the present disclosure is the alternating current (AC)and/or oscillating direct current (DC) that is used to transmit thepower 710 from the proximal circuitry (proximal electrical unit 700) tothe distal circuitry (within, part of, and/or coupled to sensorsubstrate 760), and also to carry the data signal(s) 765 from the distalcircuitry to the proximal circuitry. Carrier waves 1000 can be in theform of any waveshape that is chosen, but waves that are balanced, forexample those having the long term mean value of zero, may be preferred.Sine waves, square waves, full triangular waves, clipped triangularwaves and others are all acceptable options. For simplicity of theimplementation, and in at least one embodiment of the presentdisclosure, the use of square waves maybe preferred.

The production of the carrier wave 1000 is accomplished at the proximalside of device 100, which is where the power 710 is generated andtransmitted from. This power 710 is received and used at the distal side(by componentry of sensor substrate 760). The modulation of the carrierwave 1000 is done by the distal circuitry to superimpose the data ontothe carrier wave 1000, which is in turn demodulated by the proximalcircuitry to recover the data sent by the distal circuitry. FIGS. 31 and32 illustrate methods of production, modulation and demodulation of thecarrier wave 1000, described in further detail below.

Production of an exemplary carrier wave 1000 by the proximal circuitry(of proximal electrical unit 700) starts with the drawing of electricalcurrent from a power source 702 whose terminals are labeled as“positive” (positive terminal 3100) and “negative” (negative terminal3102) in FIG. 31 . During the first phase of the operation, switches S₁₂(also referred to herein as switch 3112) and S₁₄ (also referred toherein as switch 3114) are closed while switches S₁₁ (also referred toherein as switch 3111) and S₁₃ (also referred to herein as switch 3113)are kept open. In this phase, the electrical current (power 710) comingfrom the positive terminal 3100 of power supply 702 flows first throughthe switch S₁₂ (switch 3112) and then through guide wire 740 to reach tothe distal load. Passing through the distal load, the same current,which is now labeled as I_(s) in FIGS. 31 and 32 , passes through firstthe switch S₁₅ (also referred to herein as switch 3115), which isusually closed, and then through the tissue 730 to reach back to theproximal side (proximal electrical unit 700). As generally referencedherein, an overall device 100 of the present disclosure may be comprisedas a guide wire, with the proximal electrical unit 700 being referred toas the “proximal side” of the device 100 (configured as a guide wire)and the sensor substrate 760 being referred to as the “distal side” ofthe device 100 (configured as a guide wire). Afterwards, the current(power 710) goes through the resistor R_(s) (also referred to herein asresistor 3120) and the switch S₁₄ (switch 3114) to reach to the negativeterminal 3102 of the battery (an exemplary power source 702). It isnoted that during this first phase of the carrier wave 1000 generation,the “wire” (part of guide wire 740 distal to proximal electrical unit700) is a positive potential while the tissue 730 is at a negativepotential.

In the second phase of an exemplary carrier wave 1000 generation, theswitches S₁₂ (switch 3112) and S₁₄ (switch 3114) are kept open whileswitches S₁₁ (switch 3111) and S₁₃ (switch 3113) are closed. Thisconfiguration reverses the direction of I_(s) since the current comingfrom the positive terminal 3100 of the power supply 702 goes through S(switch 3111) and R_(s) (resistor 3120) to reach the tissue 740. Thiscurrent then goes through the switch S₁₅ (switch 3115), the distal load,the “wire” (the part of guide wire 740 between the proximal electricalunit 700 and the sensor substrate 760) and finally the switch S₁₃(switch 3113) to reach to the negative terminal 3102. During the secondphase of an exemplary carrier wave generation 1000, the “wire” (the partof guide wire 740 between the proximal electrical unit 700 and thesensor substrate 760) is a negative potential while the tissue 740 is ata positive potential. This alternation of the both potential and thedirection of the current I_(s) assures that the carrier wave 1000retains its AC nature, for example.

The modulation of the carrier wave 1000 can be done using variousdifferent arrangements, as illustrated in FIGS. 31 and 32 . Thearrangement shown in FIG. 31 utilizes a series resistor, R_(M1)(resistor 3122) to modulate the carrier wave 1000. Briefly, when theswitch S₁₅ (switch 3115) is closed, the only resistances that thecurrent IS faces are the resistance of the distal load, R_(L) and thesense resistor R_(S), giving the total resistance value of R_(L)+R_(S).If the voltage of the power supply 702 is V_(P), then the current IS canbe found using the Ohm's law:

I _(S1) =V _(P)/(R _(L) +R _(S))  [Equation 2]

When the switch S₁₅ (switch 3115) is open, the current IS must gothrough the resistances R_(L), R_(M1) and the R_(S), giving the totalresistance value of R_(L)+R_(M1)+R_(S). Again using the Ohm's law, thenew value of the current IS can be determined to be:

I _(S2) =V _(P)/(R _(L) +R _(M1) +R _(S))  [Equation 3]

Comparing Equation 2 and Equation 3, one can conclude that the I_(S2) isless than I_(S1), since the denominator of Equation 3 is larger thedenominator of the Equation 2.

The voltage drop VS over the resistor R_(S) (resistor 3120) is can becalculated for both values of the current IS as follows:

V _(S1) =R _(S) *I _(S1)=(V _(P) *R _(S))/(R _(L) +R _(S))  [Equation 4]

V _(S2) =R _(S) *I _(S2)=(V _(P) *R _(S))/(R _(L) +R _(M1) +R_(S))  [Equation 5]

Again it can be inferred that V_(S2) is less than V_(S1).

Modulation of the carrier wave is accomplished by opening and closing ofthe switch S₁₅. To transmit a data bit corresponding to a “1”, thedistal circuitry closes the switch S₁₅, which increases the value of thecurrent Is to a value of Is' and the VS increases to V_(S1), whichdetected by the proximal circuitry as data bit of “1”. Conversely, theopening of the switch S₁₅ by the distal circuitry reduces the I_(S) toI_(S2) and VS to V_(S2), leading to the detection of the “zero” bit bythe proximal circuitry.

To obtain a traditional modulation index of 10%, it is preferred thatthe values of R_(M1) and R_(S) be chosen such that the ratio of(I_(S1)−I_(S2))/I_(S1)=0.1.

The arrangement shown in FIG. 31 has the advantage of allowing the powerflow to the distal load all times, regardless of the transmission of a“one” or a “zero”, although some reduction of power is experiencedduring the transmission of a zero. It is possible to reverse thedesignations of the zero and one, for example, so that S15 is closed tosend a “zero” and opened to send a “one”.

The schematic that is shown in FIG. 32 utilizes a shunt resistor, R_(M2)(resistor 3200), to modulate the carrier wave 1000. Briefly, when theswitch S₁₆ (switch 3116) is opened, the current I_(S) has only a singlepath to take when it travels in the distal circuitry which has theresistors R_(L) and R_(S).

I _(S1) =V _(P)/(R _(L) +R _(S))  [Equation 6]

and

V _(S1) =R _(S) *I _(S1)=(V _(P) *R _(S))/(R _(L) +R _(S))  [Equation 7]

However, when the switch S₁₆ (switch 3116) is closed, the current hastwo paths to take, one through the distal load and the other through theresistor R_(M2), which reduces the total resistance.

I _(S2) =V _(P)/(R _(L) *R _(M2)/(R _(L) +R _(M2))+R _(S))  [Equation 8]

and

V _(S2) =R _(S) *I _(S2)=(V _(P) *R _(S))/(R _(L) *R _(M2)/(R _(L) +R_(M2))+R _(S))  [Equation 9]

In this schematic, switch S₁₆ (switch 3116) is usually kept open, notclosed as in the case of first schematic described earlier, to allow thefull power to be delivered to the distal load and not be lost over theshunt resistor R_(M2). Again the current I_(S) and the correspondingsense voltage VS are larger when the switch S₁₆ is closed. Choice of theswitch closure to represent a zero or a one is also arbitrary in thisschematic (FIG. 32 ) as it was with schematic (FIG. 31 ).

The first schematic (shown in FIG. 31 ) is more appropriate for asituation where the noise is low, and the reliable transmission can beaccomplished with a low modulation index since the modulationaccomplished by a further reduction of the amplitude of the carrier wave1000. For example, if the noise is only few percent of the carrier wave1000 amplitude, then a 10% reduction in the carrier wave 1000 amplitudecan easily be detected by the proximal circuitry. Then it is preferredto use the first schematic (shown in FIG. 31 ) as it reduces the powerdelivered to the distal load by approximately 10% during the times thatthe switch S₁₅ is closed.

The second schematic (shown in FIG. 32 ) is preferred when the inherentnoise level is high. This schematic increases uses a modulation byincreasing the current and the sense voltage to overcome the noise.However, it has the trade-off of dramatically reducing the current beingsupplied to the distal load during the data transmission.

Exemplary integrated circuits (ICs or ASICs, referred to herein asexemplary circuit modules 104) may include various components containedwithin sensor substrates 760 of the present disclosure. Furthermore,various circuit modules 104 of the present disclosure can be configuredand/or operable to perform the following tasks/functions, such as, butnot limited to:

-   -   a) Rectification of the AC power coming from the proximal        circuit (proximal electrical unit 700) to generate DC power that        is necessary for the operation of the distal circuitry (of,        within, or coupled to sensor substrate 760); and/or    -   b) Regulation of the DC power to reduce ripples and provide        constant voltage supply that is needed by the components of the        distal circuitry; and/or    -   c) Modulation of carrier wave 1000 for the transmission of the        data from the distal circuitry to the proximal circuitry; and/or    -   d) Detection of the interruption of the power by the proximal        circuitry, which in turn indicates that it is safe for the        distal circuitry to collect data using the sensors (sizing        portion 120 and/or sensor(s) 130) that are present at the distal        circuitry; and/or    -   e) Govern the operation of all the circuits and sensors in the        distal tip, including the power storage capacitor (capacitor        762), pressure sensor (an exemplary sensor 130), temperature        sensor (another exemplary sensor 130), and the impedance        sensor(s), such as electrodes 122, 124, 126, 128; and/or    -   f) Generate diagnostic information that can be sent back to the        proximal circuitry; and/or    -   g) Produce necessary offset voltages to the sensors and the        onboard amplifiers (such as amplifiers 914); and/or    -   h) Turn on and off the isolation switches (such as switches 930,        932, and/or other switches referenced herein) during and after        the sensory measurements respectively to reduce the interference        of the carrier wave 1000 to the data from the transducers;        and/or    -   i) Produce excitation that is necessary for the operation of the        sensors (such as electrodes 126, 128), including the AC        excitation to the electrodes 126, 128 of the impedance sensor        (sizing portion 120) and the strain gauges residing the bridge        circuit of the pressure sensor as well as the temperature        sensor; and/or    -   j) Amplify the signals coming back from the sensors (such as,        for example, by way of directing and/or regulating operation of        one or more amplifiers 914); and/or    -   k) Sample the signals coming back from the sensors at the        correct instance; and/or    -   l) Convert the analog signals coming from the sensors into a        digital format (such as, for example, by way of direction and/or        regulating operation of analog to digital converter 922); and/or    -   m) Store the digital sensor data, such as within memory 964 (an        exemplary storage medium of the present disclosure that can be        connected to circuit module 104 and/or other components of        sensor substrate 760, whereby memory 964 can store data until it        can be transmitted to the proximal circuitry; and/or    -   n) Transmit data to the proximal circuitry (such as, for        example, by way of direction and/or regulating operation of        wired or wireless communication module 600 or another part of        device 100 configured to transmit data, as referenced herein);        and/or    -   o) Interface with the optional radio frequency (RF) components        to recover power being transmitted by the proximal circuitry        using radio frequency electromagnetic waves;    -   p) Interface with the optional RF components to transmit data        using radio frequency electromagnetic waves to the proximal        circuitry;    -   q) Recognize that power from the proximal electrical unit 700        has temporarily stopped flowing to the conductor 106; and/or    -   r) Direct power from the proximal electrical unit 700 to        temporarily stop being delivered to the conductor 106.

As noted above, one or more of the following functions/tasks can becompleted using componentry inherent within circuit module 104 and/orcomponentry, such as shown in the various figures in connection withsensor substrate 760, in communication with circuit module 104.

As generally referenced herein, and in at least one embodiment of usinga device 100 of the present disclosure, portions of a pressure sensor130 (such as the half Wheatstone bridge referenced herein) can be usedas a thermistor, or a separate thermistor (sensor) can be used to obtaintemperature data, such as a threshold temperature based upon, forexample, the temperature of an injected bolus or the warming or coolingof said sensor based upon the temperature of blood. Such a thresholdtemperature can trigger operation of one or more of sizing portion 120and/or sensors 130 to obtain measurements, such as by way of directionof circuit module 104 after receiving the temperature data. Theoperation trigger can also be made after the circuit module 104 deliversa signal via carrier wave 1000 over the power signal to direct theproximal electrical unit 700 to temporarily stop delivering power to thesensor substrate 760 via conductor 106. Alternatively, the circuitmodule 106 can operate to turn power off while data is obtained and/ortransmitted back to the proximal electrical unit 700.

In at least one embodiment of a device 100 of the present disclosure,the distal componentry (of or coupled to sensor substrate 760) ispowered via the electrical current Is that is delivered through thecircuit formed by the guide wire 740 (part of device 100) and tissue 730while the data is transmitted electromagnetically, as shown in FIG. 33 .In such an embodiment, the carrier wave 1000 is not modulated by thedistal end componentry of device 100. However, it is periodicallyinterrupted to indicate to the distal circuitry that it is safe to makemeasurements from the sensors (such as sizing portion 120 and/or one ormore sensors 130) without having interference from the carrier wave1000. The resulting data is sent back to the proximal electrical unit(700) using radio frequency electromagnetic waves 3350, as shown in FIG.33 as being transmitted from a distal portion antenna 3300 of or coupledto wired or wireless communication module 600 to a proximal portionantenna 3302 of a receiver 3304 of, within, or coupled to proximalelectrical unit 700. Transmission can be done at any frequency that issuitable and permitted by regulatory agencies, but frequencies where theabsorption is high due to tissue 730 should be avoided. Furthermore,higher frequencies require shorter wavelengths, hence shorter antenna3300, 3302 lengths are preferred in various embodiments, However, athigh frequencies, the absorbance of tissue 730 may increase. Although,frequencies in the range of 10 KHz to 100 MHz can be used, frequenciesaround 64 MHz may be preferred depending on the embodiment used.

Data transmission can be accomplished by any of the known modulationschematics referenced herein, including amplitude modulation, frequencymodulation, and pulse position modulation, which are examples of themodulation schematics that can be used for the transmission of thesensory data in analog format using time division multiplexing, forexample. Similarly, amplitude shift keying, frequency shift keying andphase shift keying can be used for the transmission of the digital data.Other data techniques that can be used for transmission of information,such frequency division multiplexing are all within the scope of thepresent disclosure.

This schematic shown in FIG. 33 also allows additional data to be sentto the distal unit from the proximal unit using the same RF channel.

In an additional embodiment of the present disclosure, the distal tip ispowered via RF power delivered through the tissue 730 and the data isalso transmitted back electromagnetically, as it is shown in FIG. 34 .In this case, there is no need for the electrical loop formed by theguide wire 740 and the tissue 730, and the isolation switches (switches930, 932) are eliminated from the distal circuitry. Furthermore, sinceno carrier wave 1000 is sent from the proximal circuitry, there isneither a modulator on the distal circuitry nor a demodulator on theproximal circuitry. Instead, two RF units, one located in the proximalcircuitry and labeled as receiver 3304 and the other in the distalcircuitry and labeled as wired or wireless communication module 600 areused to transmit the power 710 from the proximal unit to the distal unitand to return data signals 765 from the distal circuit to the proximalcircuitry.

Although it is possible to build custom circuits for RF based power anddata transmission, it is also possible to use RFID chips that operate atdifferent frequencies ranging from 13 MHz to 900 MHz. In such anembodiment, the RFID device located on the distal portion of the guidewire (namely wired or wireless communication module 600 having anantenna 3302) would recover the power from the incoming RF signal, andprovide that the circuit module 104 to power it. An RFID chip would alsothen return the data back to the proximal unit.

In order to transmit the power efficiently and to receive the datareliably, the proximal circuitry or at least the antenna 3302 ofreceiver 3304 may need to be positioned near the distal tip of the guidewire.

Circuitry that is located in the distal tip (of, within, or coupled tosensor substrate 760) scans the sensors (such as sizing portion 120and/or other sensors 130) that are present on the medical device 100,and samples them one by one at the appropriate time. The time toactivate the sensors to produce the transducer data is determined by theoperation of the proximal circuitry (of, within, or coupled to proximalelectrical unit 700). The proximal circuitry periodically interrupts theoverall transmission of the power, as generally referenced herein, tothe distal circuitry by suspending the generation of the carrier wave1000. The distal circuitry continuously monitors the availability of thecarrier wave 1000 and interprets the absence of the carrier wave 1000 asan indication that it is time to activate the next sensor in line and tomake a measurement. The absence of the carrier wave 1000 serves not onlyserves as a trigger for the distal circuitry to switch into themeasurement mode (whereby sizing portion 120 and/or sensor(s) 130operate to obtain sizing, pressure, and/or temperature data), but alsoallows for the creation of an environment that is void of electricalinterference that is induced in the tissue 730 by the carrier wave 1000.The distal circuitry possesses a counter (such as within or controlledby circuit module 104) that allows it to cycle through the sensors onboard to make measurements. The measurement period that is produced bythe suspension of the carrier wave 1000 proximal is sufficiently longfor the distal circuitry to activate the sensors and the associatedelectronic amplifiers 914, wait for them to stabilize, obtain a reliablemeasurement, and convert the resulting data into a digital format usingthe on board analog-to-digital converter (ADC) 922. Finally, theresulting data is transmitted back to the proximal circuitry by themodulation of the carrier wave 1000 once the carrier wave 1000 isrestored by the proximal circuitry.

Various devices 100 and/or systems 300 of the present disclosure may usevarious formulas and/or algorithms, such as Ohm's Law and/or a distancebetween two electrodes (such as a distance between two detectionelectrodes 122, 124) used to detect within an electric field, one ormore saline injections, etc., as described in one or more of thefollowing references, wherein said devices 100 and/or systems 300 areconfigured to perform one or more of the following procedures/tasks:

(a) determining the size (cross-sectional area or diameter, for example)of a mammalian luminal organ, parallel tissue conductance within amammalian luminal organ, and/or navigation of a device within a luminalorgan, such as described within U.S. Pat. No. 7,454,244 to Kassab etal., U.S. Pat. No. 8,114,143 to Kassab et al., U.S. Pat. No. 8,082,032to Kassab et al., U.S. Patent Application Publication No. 2010/0152607of Kassab, U.S. Patent Application Publication No. 2012/0053441 ofKassab, U.S. Patent Application Publication No. 2012/0089046 of Kassabet al., U.S. Patent Application Publication No. 2012/0143078 of Kassabet al., and U.S. Patent Application Publication No. 2013/0030318 ofKassab, the entire contents of which are hereby incorporated into thepresent disclosure by reference;

(b) determining the location of one or more body lumen junctions and/orprofiles of a luminal organ, such as described within U.S. PatentApplication Publication No. 2009/0182287 of Kassab, U.S. PatentApplication Publication No. 2012/0172746 of Kassab, U.S. Pat. No.8,078,274 to Kassab, and U.S. Pat. No. 8,632,469 of Kassab, the entirecontents of which are hereby incorporated into the present disclosure byreference;

(c) ablating a tissue within a mammalian patient and/or removingstenotic lesions from a vessel, such as described within U U.S. PatentApplication Publication No. 2009/0182287 of Kassab, U.S. PatentApplication Publication No. 2010/0222786 of Kassab, U.S. PatentApplication Publication No. 2013/0282037 of Kassab, and U.S. Pat. No.8,465,452 of Kassab, the entire contents of which are herebyincorporated into the present disclosure by reference;

(d) determining the existence, potential type, and/or vulnerability of aplaque within a luminal organ, such as described within U.S. PatentApplication Publication No. 2010/0152607 of Kassab, U.S. PatentApplication Publication No. 2011/0034824 of Kassab, and U.S. Pat. No.7,818,053 to Kassab, the entire contents of which are herebyincorporated into the present disclosure by reference;

(e) determining phasic cardiac cycle measurements and determining vesselcompliance, such as described within U.S. Pat. No. 8,185,194 to Kassaband U.S. Pat. No. 8,099,161 to Kassab, the entire contents of which arehereby incorporated into the present disclosure by reference;

(f) determining the velocity of a fluid flowing through a mammalianluminal organ, such as described within U.S. Pat. No. 8,078,274 toKassab, U.S. Patent Application Publication No. 2010/0152607 of Kassab,U.S. Patent Application Publication No. 2012/0053441 of Kassab et al.,and U.S. Patent Application Publication No. 2012/0089046 of Kassab etal., the entire contents of which are hereby incorporated into thepresent disclosure by reference;

(g) sizing of valves using impedance and balloons, such as sizing avalve annulus for percutaneous valves, as described within U.S. PatentApplication Publication No. 2013/0317392 of Kassab and U.S. Pat. No.8,406,867 of Kassab, the entire contents of which are herebyincorporated into the present disclosure by reference;

(h) detecting and/or removing contrast from mammalian luminal organs,such as described within U.S. Pat. No. 8,388,604 to Kassab, the entirecontents of which are hereby incorporated into the present disclosure byreference;

(i) determining fractional flow reserve, such as described within U.S.Patent Application Publication No. 2011/0178417 of Kassab and U.S.Patent Application Publication No. 2011/0178383 of Kassab, the entirecontents of which are hereby incorporated into the present disclosure byreference; and/or

(j) to place leads within a mammalian luminal organ, such as by using adevice 100 of the present disclosure to navigate through a mammalianluminal organ to a location of interest, and using device 100 and/or asecond device to place a lead within said luminal organ.

In addition to the foregoing, various devices 100 of the presentdisclosure, and various other impedance devices as described in one ormore of the aforementioned patents and/or patent applications (such astetrapolar devices), may be operable to perform one or more of ablationof relatively small veins, such as to navigate through mammalian luminalorgans for Endovascular Laser Therapy (EVLT) for treatment of venousinsufficiency of varicose veins (cosmetic procedures), and/or to measureureter stenosis at different levels, including at level of ureteremerging from the kidney, as well as to measure the urethra/urinarybladder junction, strictures of abnormal congenital ureter in children,enlargement of ureter in pregnant women due to compression of the uterusagainst ureter, trauma with pelvic fracture, and other urologicalconditions.

While various embodiments of impedance devices with integrated circuitmodules and methods of using the same have been described inconsiderable detail herein, the embodiments are merely offered asnon-limiting examples of the disclosure described herein. It willtherefore be understood that various changes and modifications may bemade, and equivalents may be substituted for elements thereof, withoutdeparting from the scope of the present disclosure. The presentdisclosure is not intended to be exhaustive or limiting with respect tothe content thereof.

Further, in describing representative embodiments, the presentdisclosure may have presented a method and/or a process as a particularsequence of steps. However, to the extent that the method or processdoes not rely on the particular order of steps set forth therein, themethod or process should not be limited to the particular sequence ofsteps described, as other sequences of steps may be possible. Therefore,the particular order of the steps disclosed herein should not beconstrued as limitations of the present disclosure. In addition,disclosure directed to a method and/or process should not be limited tothe performance of their steps in the order written. Such sequences maybe varied and still remain within the scope of the present disclosure.

1. An impedance device, comprising: an elongated body configured for atleast partial insertion into a mammalian luminal organ of a patient, theelongated body having a first conductor extending therethrough; aproximal electrical unit operably connected to the elongated body andconfigured to deliver power along the first conductor; and a sensorsubstrate located at or near a distal end of the elongated body, thesensor substrate comprising a circuit module operably coupled to thesizing portion and the pressure sensor that are powered directly orindirectly from the power delivered through the first conductor, thecircuit module operable and/or configured to: a) direct operation of thesizing portion to obtain sizing data; b) direct operation of thepressure sensor to obtain pressure data; and c) transmit the sizing dataand/or the pressure data to the proximal electrical unit.
 2. Theimpedance device of claim 1, wherein the proximal electrical unit isfurther configured to process the sizing data and/or the pressure datafrom the circuit module.
 3. The impedance device of claim 1, wherein thefirst conductor comprises a single conductor, and wherein the circuitmodule is operable to direct operation of the sizing portion to obtainsizing data, to direct the pressure sensor to obtain pressure data, andto transmit the sizing data and/or the pressure data to the proximalelectrical unit using the power delivered along the first conductor. 4.The impedance device of claim 1, wherein the sensor substrate furthercomprises a capacitor configured to obtain the power from the proximalelectrical unit.
 5. The impedance device of claim 4, wherein the sensorsubstrate further comprises a distal power source, the distal powersource configured to charge the capacitor.
 6. The impedance device ofclaim 1, wherein the circuit module is powered by a distal power sourceof the sensor substrate, the distal power source configured to power thecircuit module using the power delivered through the first conductorand/or from a capacitor coupled to the distal power source that isconfigured to receive the power delivered through the first conductor.7. The impedance device of claim 1, wherein the sizing portion comprisesa pair of detection electrodes positioned in between a pair ofexcitation electrodes, the pair of excitation electrodes are configuredto generate an electric field detectable by the pair of detectionelectrodes.
 8. The impedance device of claim 1, wherein the sizingportion and the pressure sensor are each operably connected to amultiplexer positioned upon or within the sensor substrate.
 9. Theimpedance device of claim 1, wherein the sensor substrate transmits thesizing data and/or the pressure data to the proximal electrical unit byway of a metallic element coupled to the sensor substrate, wherein themetallic element is configured to transmit the sizing data and/or thepressure data through tissue adjacent to the mammalian luminal organ toa pad positioned upon skin of the patient.
 10. The impedance device ofclaim 1, wherein the elongated body further has a second conductorextending therethrough, wherein the power is delivered from the proximalelectrical unit to the sensor substrate using the first conductor, andwherein the sizing data and/or the pressure data is transmitted from thesensor substrate to the proximal electrical unit using the secondconductor.
 11. The impedance device of claim 1, further comprising: awrap configured to wrap around at least part of the elongated body at afirst location.
 12. The impedance device of claim 11, wherein the sizingportion comprises a plurality of electrodes configured to obtain thesizing data, and wherein the plurality of electrodes are coupled to orformed as part of the wrap.
 13. The impedance device of claim 1, whereinthe sensor substrate further comprises a temperature sensor, and whereinthe circuit module is further operable and/or configured to direct thetemperature sensor to obtain temperature data and to transmit thetemperature data to the proximal electrical unit.
 14. The impedancedevice of claim 1, wherein the elongated body and the sensor substrateeach have an outer diameter of 0.014″ or less.
 15. The impedance deviceof claim 1, wherein the circuit module is operable and/or configured totransmit the sizing data and/or the pressure data to the proximalelectrical unit by directing operation of a wireless communicationmodule configured to wirelessly transmit the sizing data and/or thepressure data to the proximal electrical unit or a component coupledthereto.
 16. The impedance device of claim 1, wherein the impedancedevice forms part of a system, the system further comprising: a padconfigured for attachment to skin of the patient and further configuredto receive the sizing data and/or the pressure data from the sensorsubstrate through tissue of the patient.
 17. An impedance device,comprising: an elongated body configured for at least partial insertioninto a mammalian luminal organ of a patient, the elongated body having afirst conductor extending therethrough; a proximal electrical unitoperably connected to the elongated body and configured to deliver poweralong the first conductor; and a sensor substrate located at or near adistal end of the elongated body, the sensor substrate comprising acircuit module operably coupled to the sizing portion and the pressuresensor that are powered directly or indirectly from the power deliveredthrough the first conductor, the circuit module operable and/orconfigured to: a) direct operation of the sizing portion to obtainsizing data; b) direct operation of the pressure sensor to obtainpressure data; and c) transmit the sizing data and/or the pressure datato the proximal electrical unit; wherein a) and b) are performed uponthe circuit module identifying that power through the single conductorfrom the proximal electrical unit has temporarily stopped.
 18. Theimpedance device of claim 17, wherein the proximal electrical unit isfurther configured to process the sizing data and/or the pressure datafrom the circuit module, and wherein the circuit module is also coupledto a temperature sensor, and wherein the circuit module is operableand/or configured to direct operation of the temperature sensor toobtain temperature data.
 19. A method, comprising: inserting a portionof an impedance device into a luminal organ of a patient, the impedancedevice comprising: an elongated body configured for at least partialinsertion into the luminal organ, the elongated body having a firstconductor extending therethrough, a proximal electrical unit operablyconnected to the elongated body and configured to deliver power throughthe first conductor, and a sensor substrate located at or near a distalend of the elongated body, the sensor substrate comprising a circuitmodule configured to direct operation of the sizing portion to obtainsizing data and the pressure sensor to obtain pressure data and furtherconfigured to transmit the sizing data and/or the pressure data to theproximal electrical unit by way of the elongated body; operating theimpedance device to obtain the sizing data and the pressure data withinthe luminal organ; transmitting one of the sizing data or the pressuredata to the proximal electrical unit; and if the sizing data wastransmitted to the proximal electrical unit, transmitting the pressuredata to the proximal electrical unit, or if the pressure data wastransmitted to the proximal electrical unit, transmitting the sizingdata to the proximal electrical unit.
 20. The method of claim 19,wherein the sizing data and/or the pressure data is transmitted to theproximal electrical unit by first transmitting the sizing data and/orthe pressure data through tissue of the patient to a pad positioned uponthe patient's skin, wherein the pad is operably connected to theproximal electrical unit.